SYL\CSL OF BIOLOGICAL DATA O1 SACCORHIZA POLYSCHIDES

pa red L;7

a'. A. NORìCk

FAO Fishr Synopsis No. 3(Distribution restricted) SAST - bIfo Laminaria - 7,77(02),012,O1

FOOD AND AGRICULTURE ORGANIZATION OF THE UNITED NATIONSROME, 1970

'4 ?I?

FO

FIRM/S83

DOCUMENTS OF THE FISHERYRESOURCES DIVISION OF FAO DE-

PARTMENT OF FISHERIES

Documents which are not officialFAO publications are issued in severalseries. They are given a restricteddistribution and this fact should beindicated if they are cited. Most ofthem are prepared as working papersfor meetings, or are summaries of infor-mation for use of member govern-ments, organizations, and specialistsconcerned.

Special groups of synopses are iden-tified by symbols followed by classifi-cation numbers based on indexed codeof "Current Bibliography":

SAST Data concerning certain spe-cies and fish stocks.

MAST Information on methods andsubjects.

01 Oceanographic data.

IT Limnological data.

and

CART Information concerning fish-eries and resources of certaincountries and regions (FID/S).

Special groups of Technical Papersare identified by:

RE Indexed lists of experts andinstitutions drawn from Regis-ters maintained by the FisheryResources Division.

CB Lists of periodicals, specialsections of "Current Bibliogra-phy for Aquatic Sciences andFisheries," special bibliogra-phies and papers concerningdocumentation problems.

MFS Provisional editions of "FAOManuals in Fisheries Science."

Some documents also have anotheridentification, if, for example, they havebeen contributed to a meeting forwhich papers have been numberedaccording to another system.

DOCUMENTS DE LA DIVISION DESRESSOURCES HALIEUTIQUES DU DÊ-PARTEMENT DES PÊCHES DE LA FAO

Des documents qui ne figurent pasparmi les publications officielles de laFAO sont publiés dans diverses séries.Ils font seulement l'objet d'une distri-bution restreinte, aussi convient-il dele préciser lorsque ces documents sontcités. II s'agit le plus souvent de do-cuments de travail préparés pour desréunions, ou de résumés d'informationà l'intention des gouvernements despays membres, ainsi que des organi-sations et spécialistes intéressés. Cesséries sont les suivantes:

Des catégories spéciales de synopsessont identifiées à l'aide de symbolessuivis des chiffres de classification ba-sés sur le code d'indexation de la«Current Bibliography «:

SAST Données sur certaines espèceset populations de poissons.

MAST Renseignements sur des mé-thodes et des sujets.

01 Données océanographiques.

IT Données limnologiques.

et

CART Renseignements sur les pêche-ries et les ressources de cer-tains pays et régions (FID/S).

Des catégories spéciales de docu-ments techniques sont identifiées àl'aide des symboles suivants:

RE Listes indexées d'experts etinstitutions tirées des registrestenus à jour par la Divisiondes ressources halieutiques.

CB Listes de périodiques, des sec-tions spéciales de la « CurrentBibliography for Aquatic Scien-ces and Fisheries «, des biblio-graphies particulières et desarticles sur les problèmes dedocumentation.

MFS Editions provisoires des « Ma-nuels FAO de science halieu-tique «.

Certains documents portent parfoisd'autres numéros d'identification, parexemple, s'ils ont été préparés pourune réunion dont les documents ont étémarqués à l'aide d'un autre système.

DOCUMENTOS DE LA DIRECCIONDE RECURSOS PESQUEROS DEL DE-PARTAMENTO DE PESCA DE LA FAO

Esta Subdirección publica varias se-ries de documentos que no puedenconsiderarse como publicaciones ofi-ciales de Ia FAO. Todos ellos tienendistribución limitada, circunstancia quedebe indicarse en el caso de ser ci-tados. La mayoría de los títulos quefiguran en dichas series son docu-mentos de trabajo preparados parareuniones o resúmenes de informacióndestinados a los estados miembros,organizaciones y especialistas intere-sados.

Grupos especiales de sinopsis sedistinguen con las siglas siguientes,seguidas por números de clasificaciónque se basan en las claves de los ín-dices de la « Current Bibliography ».

SAST Datos relativos a ciertas espe-cies y poblaciones.

MAST Sinopsis sobre métodos y ma-terias.

01 Sinopsis sobre oceanografía.

IT Sinopsis sobre limnologla.

y

CART Información sobre los recursosacuáticos vivos de algunospaíses y regiones (FID/S).

Grupos especiales de documentostécnicos se identifican por las siglassiguientes:

RE Listas índices de expertos y deinstituciones tomadas de losregistros que se llevan en laDirección de Recursos Pesque-ros.

CB Listas de periódicos, seccionesespeciales de la « Current Bi-bliography for Aquatic Scien-ces and Fisheries », bibliogra-fías especiales y trabajos rela-tivos a los problemas de docu-mentación

MFS Ediciones provisionales de los« Manuales de la FAO deCiencias Pesqueras ».

Algunos documentos tienen tambiénotra identificación si, por ejemplo, soncontribuciones a una reunión cuyosdocumentos han sido marcados conarreglo a otros sistemas.

FAO Fisheries Report FIR IR (No.)FAO Fisheries Circular FIR IC (No).FAO Fisheries Synopsis FIR IS (No).

FAO Fisheries Technical Paper FIR IT (No.)

FAO Fisheries Synopsis No. 83 FIRM/S83

(Tistribution restr.icted) SAST - bulbous Laminaria - 7,77(02),012,O1

SYNOPSIS OF BIOLOGICAL DATA

ON Saccorhisa polys chides

Prepared by

P.A, NORTON

Department of Botany, The tjniveraityGlasgow, W,2., Scotland

FOOD AND AGRICULTURE ORGAIUZATION OF THE UNITED NATIONSRome, October 1970

Distribution

FAO Depar-tment of FisheriesFAO Regional Fisheries OfficersRegional Fisheries Councils andCommissionsSelector S1.

Author

PREPARATION OF THIS SYNOPSIS

This is the first in a series of species synopsis on biological data of large brownseaweeds which are knoin for their importance in the kelp industry and as a source of rawmaterial for a].ginio acid and alginates.

The material presented in this synopsis is based on data collected by the author inthe course of personal research work on the species and also, on information received fromvarious sources, most of which are listed in the Bibliography.

"Current Bibliography'1 entry

Norton T,A. (1970) 1 7-6M350FAO Fish.Synops., (83):pag.var,Synopsis of biological data onSaccorhiza polysehides

ARE, ASE. Laminariaceae - biologicalsynopsis. Taxonomy, morpholo, geographicaland ecological distribution. Chemicalcomposition, Metabolism, nutrition, growth.Life cycle, reproduction, phenoloy,Population - structure, density, mortality,standing crop, Harvesting techniques,seasons, yields. Protection and management,Utilization - food, fodder, industrialproducts. Selected bibliography.

FIRN/583 bulbous Laminaria iii

1.1 Nomenclature

1.11 Valid, scientific name1 .12 Nomenclatural synonyms1.13 Vernacular names

1,2 Taxonomy i

1.21 Affinities1,22 Subspecies

1.23 Genetic data

1,3 Morphology and anatomy 2

1,31 External inorpholor 21.32 Anatomy 2

2 DISTRIBUTION, ECOLOGY AND ?'1EPABOLI SM 2:1

2,1 Total area

2,2 Local vertical and horizontal diatríbution 1

2.3 Effects of ecological determinants 1

2,4 Nutrition and growth 3

2,41 Assimilation 3

2.42 Respiration 3

2.43 Nutrition 32,44 Growth 3

3 LIFE RISTORY 3:1

3,1 Life Cycle i

3.11 Alternation of generations 1

3.12 Nuclear phases 1

3,2 roduction 1

3,3 Phenology 3

3.31 Seasonal variation in external appearance and morpholor 33.32 Seasonal variation in total fresh and dry weight*

3,33 Seasonal variation in other characteriatics*

4 POPULATION 4:1

4.1 Structure

4,11 Age composition

CONTENTSPage No.

1 IDENTITY 1:1

iv FIRM 683 bulbous Laminaria

4,12 Weight or size composition*4.13 Sporophrtegamotophyte and sex oomposition*

Page No.

4,21 Avertre densities of defined areas 1

4,22 Variation in density with ecological and accidental factors*

4,3 Mortality, morbidity

4.4 Total uantities (standing crop) of defined areas 1

4,5 Accompanying and competing species 1

5 HARVESTING 5:1

5,1 Method8ofHarvestin I

5.2 Harvesting_rdoaonB 1

5.3 Harvesting areas and depths 1

5.4 Regrowth on harvested areas 1

5.5 Total annual yields*

6 PROTECTION AND MANAGENENT 6:1

6.1 Official roulaions*

6.2 Control of physical features*

6.3 Control of chemical features*

6.31 Water pollution*6.32 Artificial fertiliation*

64 Control of biological features 1

6.41 Control of pre.tion and competition6.42 Population manipulation*

6.5 Artificial culture i

7 CHEMICAL COMPOSITION 7:1

7,1 Water content 1

7.2 Inorganic constituents I

7,3 Organic constituents 3

7,31 Carbohydrates 3

7,32 Proteins*7.33 Fat*7.34 Pigments*7.35 Other or io constituents 3

4.2 Density 4:1

FIBM/S83 bulbous Laminaria y

8 UTILIZLPION

8,1 Human food*

8.2 Animal fodder

8.3 Manure

8,4 Industrial products

9 REFERENC

Page No.

8 i

* As no information was available to the author these items have been omitted from the text,

FIRM 583 bulbous Laminaria

1 IDENTITY

1.1 Nomenclature

1,11 valid scientific name

Saccorhiza polyachides (Lightf.) Dati, 1902,A catalogue of the British Marine Algae.

1,12 Nomenclatural synonyms

The first binomial applied to this specieswas Fucus polyschides Lightfoot 1777, FloraScotica volume 2, p.936.

Other synonyms for this species are:

Fucus bulbosus Hudson 1778, p, 579Ulva bulbosa Beauvois May 1805, p,20, plate 13Ts U. tuberosa)

tJlva bulbosa (Huds,) Lamark et de Candolle Sept,T05, p.16 nom, illeg,

Diva tuberosa Beauvois Nay 1805, plate 13 prosyrion. nom, illeg.yschides bulbosa (Huds,) Stackhouse 1809, p,66

Laminaria bulbosa (Hudz,) Lamouroux 1813, p.22Laminaria belvisii C, A:rdh 1820, p.115, nom.

nov. = Uiva bulbosa Beauv, non. U. bulbosa(Buds,) Lamark & D.C.

Laminaria elliptica C. Agardh 1820, p.119Laminaria plmcta-ta Dory 1826, p.190Laminaria turnen Bory 1826, p.190Saccorhiza bulbosa (Hude,) Do La Pylaie 1829, p.23

jnla bulbosa (Huds,) Decaisne 1842, p.345Phycocastanuni bulbosuni (Huds,) Kitzing 1843, p.346Saocorhiza olliptica (C. Ag.) Cruoan 1852, no.87

1,13 Vernacular names

The popular names given -to this speciesinclude:

British Isles: bulbous Laminaria, bulbous-rootedtangle, furbelows, sea furbolows, great fur-lowed Laminaria, furbelowed hangers

Norway: sekktare

Portugal: carocha, caixeira, cintas9 golfe orgolfo, iimo-corroia, limo-corriola

1.2 Taxonomy

1,21 Affinities

Sup ragene ri o

Saccorhiza polyschides (Lightf,,) Batters(1902) belongs to the family Laminariacoae ofthe order Laminariales of the division Phaeophyta,

Generic

The genus Saccorhiza was established by de laPylaie in 1829 (Flore de L'ue de Terre Neuve et

1:1

les iba St, Pierre et Miolon p.23), The typespecies of the genus s Saccorhioa bulbosa (Huds.)de la Fyi. a synonym for S, poiyschideÇLightf.)Bait,

The sporophytos o.? the genus are annualplants, They are characterised by a lamina whichlacks a midrib but possesoes clyptootomata, Thestipe is flattened end develops a dis-tinot sub-sidiary holdíast r'bove the original at-tchmontorgan, The unibocular sporangia of Lertile spo--rophytes each contain 128 zoosporee, The para-physee which are aleo found in the reproductiveson are devoid of the hyaline tips found on thoseof Laminaria,

Specific

The type of -the species is Fucus polyschidocLightfoot collec-tcd ftom -the Island of lona, Westof Scotland, Lectoype material io located inthe Herbarium of the British Museum, London.

The sporophyte of this apecies io roadilydistinguished from those of Lemnania by thecryptostomata on -the larnina he flatiened andbasally -twisted stipe, th reproductive frills onthe sides of the stipe and the large basal 9bulbiwhich is quite unlike the holftfast of Laminaria,

The only other species included in the genusis S. dermatodea, a species largely confined tothe Arctic Ocean, The geographical distributionof the two species does no-t overlap, Recent cul-turo studies of S. derrnatodea have confirmed itsaffinities with S, polyschdes (Norton, 1970),

Key to the species of Saccorhiza:

Lamina of sporophyte en-tire or divided into30 or more digits, stipe long, up to 210 cm x8 cm, twisted at base and in adult plant bearingundulating lateral extensions; secondary hold-fas-t a hollow bulbous expansion up to 30 cm indiameter, bearing numerous whorls of imbranchedhaptera, . .. .5. yschidos,

Lamina en-tire or divided into only 4 to 5digits, stipe short up to 60 x 2 cm, lackingbasal twist and lateral undulations; secondaryholdfast a small umbrella-shaped expansion up to5 cre in diameter, bearing only two whorls ofhaptera which may be branched,,.,, 5. dermatodea,

1.22 Subspecies

No subspecies are recognised by the presentau-thor,

1,23 Genetic data

Some aspects of the cytology of S. poly-.schides have been examined by Evans (1965) usingsodified acetocarmine squash methods and Feulgensquashes, He found that the nuclei of S. poly-

schid.es were larger than those of the other lamina-nana he examined, The nuclei of the female game-tophytes were 8-14im in diameter, with a nucleolusof 3-4mi whilst the nuclei of the rile game-tophy-teswere 2.5-4.2im in diameter, There was an increasein nucleus size prior to oogonial formation andoogonial nuclei of 18un in diameter were not un-common,

The number of chromosomes in . polyschides isreported to be 62 in the diploid state and 31 inthe haplold state (Evans 1965), Although thechromosomes varied in size, in the female gameto-phyte the majority were between 0.8pm and 1.mlong, but there was always a very large chromosome4jum-.6pim long. This was desig ted the X-chromo-some by Evans (1965). It stained well withSchiff's reagent and was present in the cells offemale etophytes and of young sporophytes, butwas not found in male gametophytes, Evans (1965)postulated that there is probably an X/Y sex-determining mechanism in S. polyschides and thatsex segregation takes place at the first meioticdivision during spore formation. It is thereforeprobable that the zoospores from a single spor-angium produce equal numbers of male and femalegarnet ophyt es.

1.3 Morphology and anatomy

1.31 External morpholor

The thallus is pale dark brown in colour andis clearly differentiated in-to lamina stipe andholdfast (Fig, i). The lamina bears characteris-tic cryptostoma-ta and may reach 150 cm or more inlength. The stipe is flattened and twisted to-wards its base. It may measure up to 210 cm longand 8 cm wide. The stipe of the adult plantusually bears undulating lateral extensions, thereproductive frills. Obscuring the originalLaininania-like holdfast is the 'bulb', a hollowbulbous expansion up io 30 cm in diameter. It iscovered with short protruberances above arid at-tached by unbranched haptera below.

The appearance of the sporophyte variesgreatly. At the Isle of Man and in South-WestIreland Norton (1969) observed striking differencesin the morpholo and the anatomy of sporophytesgrowing in different, although sometimes adjacenthabitats. The variations were found to be as-sociated with the different environmental condi-tions in the various habitats, and especially withthe degree and typo of water movements to whichthe plants were subjected. In areas of weak cur-rent the plants produced broad, curved blades,distinctly cordate at the base, devoid of digitsand so flimsy that they tore under their ownweight when removed from the water. In contrast,plants growing in strong currents developed verylong, flat, tough blades, cuneate at the base anddivided into 30 or more digits. In habitatswithout current but exposed to wave action, thesporophytes possessed short, flat extremely toughblades with few, usually only 3-10, digits.

It was found that the greater touginess ofthe blades in plants from areas of current, andmore particularly turbulence, was the result ofa larger number of cortical cells increasing thethickness of the thallus. Experiments in cul-ture and transplants of labelled sporophy-tes inthe sea indicated that these variations in mor-phology and anatomy were phenotypically basedrather than genotypically selected. Sporestaken from plants growing in three localitieswere cultured together under identical conditionsfor over six mon-the. By this time, the largestof the resultant sporophytes wore 32 cm long and,in contrast to the disiinctiona which would havearisen after a similar period of growth in theirnatural habitats, the plants were iridistinguish-able. In addition, young sporophy-tea weretransplanted from one locality to another in thesea. Wi-thin 12 weeks of transplanting, the ape-rophy-tes had completely changed their morpholoand had become indistinguishable from the controlplants native to that habitat (Norton 1969).

1.32 Anatomy

The primary growth of the sporophyte resultsfrom cell divisions in the intercalary menistemwhich is situated at the junction of stipe andlamina, The menistem gives rise to new laminatissue above and new a-tipe tissue below. Bothstipe and lamina are essentially similar in trans-verse section. They are composed of a centralmedulla, a surrounding cortex and a peripheralmenistoderm (Fig. 2). The superficial moniato-denia is composed of small, cubical cells full ofchromatophores and with a thicken outer wall.The cortical cells become larger towards thecentre of the section, but their size and thenumber of cell rows depends upon the stage ofdevelopment of the plant and upon the region ofthe plant from which the section is taken. Intransverse section (Fig. 2) the cortical cellsare usually square or rectangular in shape butin longitudinal section they are progressivelymore elongated towards the medulla. The dis-tinction between cortex and medulla is not clear-cut, for -the cortical cells adjacent to themedulla aro distorted and merge with the medul-lary tissue. The medullary elements are oftenseptate and branched and are invariably muchelongated and predominantly longitudinal inarrangement. They also possess thick mucilagi-nous walls. None of the sieve-tube like ele-ments which have been described in Laminariasaccharina (Sykes 1908) are found in S. £2Y-sohides, nor are there any mucilage ducts in thecortex, such as those found in Laminaria hyper-borea and in the blade of L, sacoharina. Al-though transverse sections through both stipeand blade show essentially similar structures,one taken across a hapteron is fundamentally dif-ferent (Barber 1889).

The meristem of the transition zone appearsto be the primary source of new cells, but theperipheral menistoderm also retains its menate-

1:2 FIRM S83 bulbous Laminaria

FIRM S83 bulbous Laminaria 1:3

Lamina

Fla ed Stllp

eîricthr Frill

Fig, i A drawing of the adult sporophrte of S. polyschides showingthe distinctive morphological features of the species

Twisted Base of.StpeBulb

oo

oo

ou

ç

200»

'o

o

o

Fig. 2 A transverGo section taken across the base of thelamina of a 22-.week old sporophrto grown in culture

1:4 ,s8 bu1boii Li.via

00C) cP =_o

YIR S8 bulbous Laminaria 1:

sop

Fig, 3 The microscopic sts in the life history of S. £2.yschides

25p

A A vertical section through a sorus on the lamina; C Female gametophy-tes; the stipplod area rep-the darker bodies are the spores in the sporangia resents the tissue of the developing sporophytewhich are surrowided by sterile paraphyses

B Male gametophytes bearing antheridiaD A 28day old sporophyto with several rhizoidz

126 FIRM S83 bulbous Laninaria

matie activity and adds to the length of the thai-lus by means of transverse divisions and to itsgirth by cutting off new cortical oeils t en-tially. Th cortical cells seem to be unable todivide but are capable of considerable extensionin a longitudinal plane. Thus, as the frond in-creases in length the meristoderm cells tend toretain their size and shape by repeated divisions.The cortical cells on the other hand become gra-dually more elongated until they eventually becomedistorted, swollen with mucilage, and lose theircellular appearance, thereby contributing moreelements to the medulla,

The medullary elements also appear to havelittle meristematic activity and, as the surround-ing tissues expand, they too are passivelystretched. The chief distinction between the at-tenuated medullary elements and the innermost lay-ers of the cortex is the copious production ofmucilage by the former,

Other elements are also found in the medullaof S. polyachides. Septate cross connectionsare apparent in transverse section (Fig, 2).According to Sauvageau (1915) they are derivedfrom the fusion of protrusions from the longi-tudinal walls of the innermost cortical cells.Hyphae are also produced. They differ from thecross connections in that they do not fuse witheach other. The hyphae extend in all directionsbetween the other elements but they are pre-dominantly radial and must contribute to thestrength of the thallus without greatly limitingits flexibility.

In mature plants the reproductive son de-

velop on the surface of the thallus ai the baseof the lamina, on the frills and on the bulb.The seri are composed of unilocular sporangiainterspersed with sterile paraphyses (Fig. 3A).Mature sporangia reaches i 2im long and 2Opxnwide. Each sporangium produces 128 zoospores.

8: bulbou Laminaria 2:1

2 DISThIBUTION, ECOLOGY A11) MF7PABOLISM

2,1 Total Area

S. polyschides is found all around the BritishIsles and on the Atlantic coasts of Norway, Franco,Spain, Portu&l and Morocco. (Fig, 4),

The northern limit of the species was estab-lished by Grenager (1955) at approximately 65°30'N.on the Norwegian coast, 225 km north of Trondheim,The species has not been found in the Arctic Circle,

The southernmost limit of the species wouldappear to be on the west coast of Africa. Thespecies is recorded from Morocco (Dangeard 1949,Gayral 1958) and is reputed to occur as far southas the Rio de Oro, Spanish Sahara (Feldman 1951)and Shama, Ghana (Beauvois 1805), Beauvois' re-cord is substantiated by a specimen of S, poly-schides (in the Horneman herbarium at copenhagen)which was sent by Beauvois from the coast of Guinea,

In the Mediterranean, S. polysohides is notusually found further east than Malaga, Spain, lat.36°50'N, long. 4°50'W, (Seoane 1966) and Melilla,Spanish Morocco, lat, 35°17'N long. 2°57'W.(Bellen 1925). Bornet (1892 reported the speciesfrom Italy at Portofino and in the Stretto di Mes-sina, and Funk (1927) reported a specimen fromNaples. Sauvageau (1918) emphasised that recordsfrom the Mediterranean were only isolated occur-rences, the species being unable to maintain itselfin this region. However, Meunier and Picard(1953) reported that S, polysohides had establisheditself in the region of Messina. They regardedthis population as a recent introduction resultingfrom the installation of artificial substrates aridthe increase in shipping in the area,

2.2 Local vertical and horizontaldistribution

S. polyschides is usually epilithic, but insheltered-water localities at both Port Erin, Isleof Man, and Lough me, Ireland, it also growsloose-lying, attached only to small stones orshells, The species is usually, but not in-variably, found in turbulent-water habitats and ischaracteristically abundant in areas subject tocurrent. It is confined to the sublittoral region;even the uppermost plants in the Saccorhiza zoneare only exposed by the Etreme Low Water of SpringTides (E.L,W.S.),

The deepest attached plants of S, polyschidesfound by the author were 15 rs below E.L,W,S, atCarsaig in Argyll, on the west coast of Scotland(McAllister, Norton and Conway 1967), In the Isleof Man, Kam (1960) recorded attached plante ofthis species down to 19 m and during the presentwork loose-lying specimens were found to survive ina healthy state at a depth of 24 rs in Bay Fine,near to Port Erin. Isolated individuals have beenreported from depths of 30-35 rs by John (1968) inCornwall.

Lewis (1964) stated that S. polyachides waousually found growing at a level immediately be-low that of Alaria esculcnta or Laminaria digitata,but above that of Laminaria hyperborea,, Howeverat Port Erin end at several seaward stations onthe coast adjacent to Lough me, Ireland, S. pol-schides was invariably found belox the L.hyperbore'azone. On Port Eriri breakwater, the L. erboreazone ended abruptly at approximately 6 m belowE.L.WOS, Whatever factors controlled the lowerlimit of this species, they did not appear to af-fect S. polyschides which was most abundant im-mediately below the L. hyperborea zone and extendeddown to a depth of 8 rs.

2.3 Effects of ecological determinants

The environmental factors most likely to beresponsible for the geographical distribution ofS. polyschides are sea temperature, light andsalinity,

The northern limits of the geographical dis-tribution of S. polyschides seem to be most prob-ably controlled by the low winter water tempera-tures or the six months Arctic night, In culturesporophyte production was inhibited and the game-tophrtes progressively lost their aility to formsporopbyies at a temperature only 2 C below thatat which the plants survive at the northern limitof their distribution, On the other hand, a-though a low light intensity of 37 cal./cmsec had no effect on the ability of the gameto-phytes to produce sporophytes, it subaeqientlyinhibited the growth of sporophytes,

The southern limita of distribution arid thesparsity of the species in the Mediterranean maybe related to the high water temperatures duringthe summer, In culture the plante were adverselyaffected by a temperature of 21-26 C. Only afew abnormal sporophytes developed arid they quicklysuccumbed to contamination,

S. polyschides is not found in areas of re-duced salinity and is completely absent from theBaltic Sea, In culture, the species was foundto develop at a progressively slower rate at lowersalinities and development was irreversibly in-hibited at salinities below 9 ¡co (Norton andSouth 1969),

The environmental factors most likely to beresponsible for the local distribution of thespecies aro desiccation and grazing.

As S. pyschidec ia confined to the sub-littoral zona it would seem that the planta areunable to survive ai a level where they would besubjected to the extreme fluctuations in condi-tions associated with the intertidal region. AtLough Ine, Ireland, in August 1964, the authorobserved that when large numbers of sporophyteswere exposed io air by E.L.W,S, during a hotsummer's day, the majority of the plants driedout rapidly and. wore killed.

22 FIRM S83 bulboue Lamiiaria

a

Fig. 4 The geographical dlitribution of S. poi schides

The major grazing animals influencing thedistribution of S. polyschides aro the echinodermsEchinus eaculontus and Paracentrotus lividus. Kamand Jones (1966) have shotn that on Port Erin break-water, the lower limit of the Saccorhiza zone wasat least partly controlled by the grazing pressureof the sea-urchin Echinus esculentus which feeds onboth the gametophytes and. sporophytes. The re-moval of the echinoderms enabled S. polyschides tocolonise the lowermost available rocks, at a depthof 11 m below E.L,W.S., thus extending its depthrange in this habitat by 3 m, Similarly Norton(unpublished) has found that grazing by Paracentro-tus lividus is a major factor excluding S. poly-

iides from Lough lue in Southern Ireland0

Herbivorous gastropods also feed on S. polj-schides. Patina pellucida rasps out characteristicdeep pockets in the host tissue. Such excavationsundoubtedly weaken the plant and render it morelikely to be damaged by wave action. The laminaeof sporophytes at a locality near to Lough mewere extremely tattered owing to the ravages of P.pellucida and Lacuna vincta which were very abun-dant on the fronds (Norton 1970a).

2.4 Nutrition and Growth

2.41 Assimilation and2,42 Respiration

There has been little work on these aspectsof the physiolor of S. jyschidos. However,Kam (1969) determined the minimum irradiance re-quired for the growth of microscopic sporophytes.This is likely to be almost the same ag the compen-sation point. A-t a temperature of 10 C the mini-mum irradiance required fo growth in culture wasbetween 1 and 3 ug cal,/cm sec(10-30 lux in day-light) (Kam 1969). There is however, some evi-dence that the minimum irradiance for growth ishigher for macroscopic sporophytes (Norton andBurrows 1969a).

2.43 Nutrition

Again, little information is available, Someindication of the plants' requirements may begained, from a consideration of the media in whichthey have been successfully cultured, Unfortu-nately they have never been cultivated in a definedmedium, The present author found that they grewwell in sea water to which were added soil-extract,solutions of sodium nitrate, sodium phosphate andthe range of trace elements and vitamins listed inthe ASP2 medium of Provasoli, McLaughlin and Droop

(1957).

2,44 Growth

The growth rates of microscopic sporophytes ofS. polyschides have been investigated by Kam

T1969). It would seem that blow saturation ir-radiance (about 50 ig cal./cm. sec at 10°C) thereis a straight-line relationship between coli divi-

sions per day and irradiance., There is also astraight-line relationship between the logarithmof the sporophyte length and the lorithm ofthe number of cells per sporophyte, up to 1,000cells when the sporophyte becomes poiystromatic(Kam 1969),

The rate of thallus extension of macroscopicsporophy-tes has been determined by the presentauthor in two ways: on the mean increase inplant size of a population and on the basis ofmeasurements of marked individual sporophytes.

Table I gives the statistical analysis ofthe mean measurements of stipe length, stipewidth and blade length of monthly samples of S.polysohides sporophy-tes taken from Port Erinbreakwater. The annual cycle of the develop-ment and decay of the sporophyte is clearly seen.The maximum inorease in mean blade length was249 nun from June to July 1965 (Table I). Thisrepresents a mean rate of frond extension of62 mm per week and the rate of increase of thefastest growing plants was probably far higherthan this, A maximum increase in mean stipelength of 117 mm was recorded between June andAugust 1964 (Table I); a mean rate of stipe ex-tension of only 13 mm per tieek.

Individual sporophytes of S. polyschideswere marked and measured at monthly intervals(Norton and Burrows 1969), A total of 68plants -rere labelled and remeasured at Port Erin,Isle of Maxi and 101 plants at Lough me, CountyCork, Ireland, Although the rates of thallusextension -they recorded were somewhat variable,certain generalisations emerged, Firstly, byfar the greatest increase in blade length wasfound to occur in the proximal 25 mm immediatelyabove the meristem, In the vast majority ofsporophyten no measurable increase occurredfurther than 75 mm from the meristem. Secondly,there was an interrelationship between extensiongrowth, fruiting, and the rotting of the thalluswhich followed maturity. The rate of blade ex-tension was most rapid in juvenile sporophy-tesand rates of up to 145 mm/week were recorded,Many of the increases were however, minimalreadings, for as a result of distal decay someof the punched holes for measuring blade in-crease were lost, The rate at which new tissueas added decreased as the plant became larger,

until eventually it stopped altogether. Thispoint appeared to coincide with the beginning ofthe fruiting period. Not a single fertile spo-rophy-te was found that was growing measurably.Moreover, although the distal decay of the thal-lus appeared to follow fruiting, it was in facta more or less continuous process which only be-came apparent when growth ceased and the bladebegan to shorten,

FIRN/S83 bulbous Laminaria 2:3

2:4 FTRM S83 buJ.bous Laminaria

TABLE I

Statistical data from the analysis of measurementsof sporophytes in monthly samples taken from the

S. polysohides population on Port Erin Breakwater

MonthMean

in rum

Rangein mm

StandardDeviation

Standarderror ofthe mean

Stipe length

1964 June 83.0 1.00 - 400 10,60 1,50August 200.0 1.00 - 560 15.64 2.21October 157.0 3.00 - 470 11,19 1.69November 117.0 0 - 470 11,39 1.61December 109.0 0 - 400 17.87 2.51

1965 March 74.8 0 - 330 9.76 1.38April 77.2 0 - 360 10.98 1.55June 10,0 5.00 - 20 - -July 41.2 5,00 - 290 8.43 1,19October 229.0 35,00 - 510 12.18 1.72

Stipe width

Juno 6,1 1.00 - 20 0.51 0,071964August 8,8 2,5 30 0,79 0,11October 13,5 2.5 30 0,69 0.10November 6.6 0 20 0,57 0.08December 1,2 O 2,5 -

1965 March 1,0 0 - 2.5April 0.6 O 2.5June 5.0 O O OJuly 10,0 O 0 0October 14,0 2.5 30 0,78 0,14

Blade length

June 180,0 10,0 560 12,30 1,741964August 322,0 30.0 750 16.21 2,30October 315,0 O - 730 14,55 2.06November 147,0 0 - 510 13,28 1,88December 142,0 0 -430 13.11 1.86

1965 March 136,0 0 - 500 13.24 1,87April 122.0 0 - 500 15,27 2,16June 191,0 15.0 -440 21.17 2.99July 440,0 70.0 -1010 30,45 4.30October 379.0 0 - 810 16.21 2,30

FIEN/s8 bulbous Laminaria 3:1

3 LIFE HISTORY

3.1 Life Cycle

3,11 Alternation of generations

S. polysohides exhibits a typical Laxninarianlife history in which a macroBcopic eporophytealternates with microscopic, ctioecious gameto-phytes,

3.12 Nuclear phases

The aporophyte is diploid, the metophytesare haploid. Evans (1965) has shown that meiosisoccurs in the development of the sporangium. Thezoospores are therefore haploid and the diploicistate is restored at the fusion of gametes.

3,2 Reproduction

The reproduction of S. yschides has beendescribed from culture by Norton and Burrows

(1969), They found that the dovelopmont of thedioecious gametophytes from spores, the productionof sporophytes and their subsequent developmentwas a continuous sequence of events without a restirig stage.

The pale, motile zoospores are pear-shaped,

5 ¡um in diameter and each is furnished with asingle eye spot, a plate-like chromatophore andtwo unequal, laterally inserted fi lia. Threlease of zoospores has been described by Nortonand Burrows (1969), The eporangium was seen toburst at its apex and to e'udo a long mucilaginousenvelope which rounded off immediately after extrusion, The active, bifl&llate zoosporos rc-named together only momentarily before stammiugaway, following spiral pe.ihs. Ripe sporengadissected out from the sorus were not observed toburst and release their spores, This perhapscorroborates Schreiber's (1930) suggestion thatthe pressure of the surrounding eporaxigia may con-tribute to debiscence,

In undisturbed medium the soospores settleafter only o few hours of motility, None remainplanktonic after 24 hours, The swarmers are fur-nished with a pimontod eye spot end are photo-sensitive. When subjected to unilateral illumina-tion in the laboratory, they invariably settleaway from the light and they may therefore be con-sidered to be photonegative.

After settlement, the zoospores terminate toproduc retophytes at water tempere.tures rangingfrom 22C-26°C and at lieht intensities from 37 pigcal/cm sec-275ig cal/em'soc. Under conditions offull salinity, the percentage of spores that ter-minate is in the region of 76%, but at reducedsalinities the percentage germination is dras-tically reduced. Loss than 1% of spores germinateat a salinity of 110/00 and there is no developmentwhatsoever at salinities below 90/00 (Norton andSouth 1969).

The microscopic gametophytos may be unicel-lular or filamentous and branched (Fig. 3),The male gametophytes oro more branched than thefemale gametophytes and have more numerous, palercells. The cells of the female gamotophytesare usually 1419pim in diameter and 1-2 times aslong as broad, whereas the cells of the male

etophy-tes are only 9-11un in diameter and areup to several times as long as broad, Often,in culture, the female e-tophy-te is confinedto a single cell which acts as an oogoniuln andextrudes a singlo egg measuring 11 x 22pm. Themale ganetophyte produces clusters of tiny, coni-cal an-theridia each of which produces a singlebifiagellate antherozoid measuring approxiatoly5 pin in diameter. At a temperature of 10 Cgametangia are usually produced within 10-12 days,

The antherosoid is released by the apicaldehiscence 01' the snheridium. Similarly, theegg is extruded from the oogonium which burstsat its apex, The egg is not usually released,but remains perched on the empty ooganium duringthe early development of the sporophyte. peri-mental work in culture suggests that the gametescan be produced and released over a similar rangeof tempero-tures, light inicnsi-ties and salinitiesto those suitnbïø for spore germine-Lien, Theminimum irredionce for the maLurity of metesis 3 pig cal0/cu2isc (30 ]ix in daylight),

Mter fer-tU irion the sygoto sea] la endelongates, It diri des repecdly frsi trans-versely thon also longitudinally jo Droduce theyoung erorophyto, The bean]. cells dve1op intocolourless rhiscids to attach the devoloningsporophy-to, Ie?1 stoma t je cc Livity grathially be--

comes concentrated touards the bao o the plantwhich bocones polys-tronatie as rL increases insize,

-

The easonel behaviour of S, olyschides atPort Erin Isle of flan, ho-s been described byNorton and Burrows (1969), The percentage ofaporophytes at different stages of developmentend -the percentage fruiting in monthly samplestoken from Port Erin Breakwater is shown inTable II, Ill-though juvenile pianto wore preasn-toil -the year round there was clearly on annualcycle tu th no overlap between the now generationof sporophy-tos end -the decaying bulbs of -the pre-vioua season, The motu generation of oporophy-tsafirst beceme evident in lato tiny, After a periodof rapid growth during -the summer, the onset offruiting in October coincided with the cessationof growth, The pez-centage of the porophytestha-t were fruiting steadily increased throughoutthe autumn and winter until it reached a mezimumin Ilarcli, By flay, the proportion fruiting haddropped -to only 2%,

Phillips (1896) was one of the first workersto suggest that S, rschides was en annualspecies, Previous workers had considered it tobe perennial as -they had found adult sporopliytcs

3:2 FIRM S83 bulbous Laminaria

TABLE II

The porcentc of sporophy-tes at three sts in developmentand the percentage fruiting in monthly samples taken from the

S polyschides population on Port Erin breakwater

Months Juveniles Complete adulta Stipeleas bulbs Fruiting

1964

J 32 54 14 22

F 40 28 32 42

M 43 9 48 53

A

M 40 60 0 2

J 60 40 0 2

J 90 10 0 2

A

s

72 28 0 10

0 52 46 2 24

N 52 12 36 34

D 30 18 52 48

1965

J -F 30 16 54 56

M 24 16 60 64

A 28 14 58 60

M 30 70 0 2

J 98 2 0 0

J 94 6 0 0

A

5 64 36 0 15

0 42 55 3 22

F 40 30 30 38

at all times of year. Phillips (1896), however,clearly stated that although the majority of theplants in a population overwinierod as stipelessbulbs, some healthy sporophytes also survived thewinier. Spence (1918) in Orkney reported the per-sistence of large complete plants into the summerof their second year. This led him to describeS. polyachides as not so much an annual as a mono-carpio plant, On Port Erin Breakwater too, inaddition to the stipeless bulbs, some complete spo-rophytes overwintered. These plants did not fruitin the autumn with the majority of the populationand the observation of labelled individuals showedthat they did not become fertile until the follow-ing simmer.

A study of the literature suggests that theseasonal cycle is essentially similar in variousparts of the species' geographical range. Youngsporophytes arose in May and lost their stipes byNovember in Norway (Prints 1926; Svendsen 1962)and Orkney (Spence 1918). In other localitiessuch as Anglesey (Phillips 1896) arid Northernii'rance (Sauvageau 1918) the sequence was the same,but it began in mid-March. In all of these locali-ties as well as in Morocco (Gayral 1958) the stipe-less bulb overwinters.

The difference in the time at which the newpopulation arises in different localities can beaccounted for by seasonal rather than latitudinaldifferences, for in 1955, an exceptionally calmarid sunny year, Burrows (1958) reported that S.2yschides plants first became evident in March

at Port Erin. It should be noted that at PortErin the climatic conditions, including watertemperature, were very similar in both 1964 and1965. This may account for the close similarityin the timing of the seasonal cycle in the twoyears.

S. polysohides seemed to be incapable of re-suming growth after fruiting; no sooner had fruit-ing begun than decay became apparent on the bladeand then on the stipe, both of which were subse-'ojuently lost. Fruiting bulbs, however, persistedthroughout the winter until they too decayed andthe majority became detached from the substrate byMarch. The overwintering, stipeless, bulbs werefound to be capable of releasing viable zoosporesthroughout the winter months, even in March whenparts of the bulbs were rotting. Whether, infact zoospores were being released from the bulbsin nature is not known, but it seems likely that-they were. If spores were being shod in the fieldthroughout the winter, the bulbs must supply a vastreservoir of material from which the new populationof the following spring may be derived.

Little information could be gained from theliterature regarding possible differences in thefruiting period in different localities, for mostauthors failed to distinguish between the newgeneration of sporophytes and those which had arisenin the previous year arid overwintered. The only

clear accounts are those of Printz (1926) andSveridsen (1962), both working in Norway, where,as at Port Erin, the overwintering plants beganto fruit in July and August. The majority ofthe plants, however, lost their stipes by Novem-ber and overwintered as bulbs. In Morocco,Gayral (1958) reported that here too the plantsdecayed in the autumn and only the bulbs survivedthe winter "to bud" in the following spring.However, the exact meaning of the term bourgeoner(translated as "to bud") in this context is notclear. These references would seem to indicatethat in two very different localities, at oppositeends of the geographical ran of S. polyschides,the species exhibited a similar seasonal cycleto that described at Port Erin,

Norton and Burrows (1969a) have investigatedthe envirorunen-tal factors which may initiate thedevelopment of macroscopic plants of S. poly-sohides in the spring. They concluded on thebasis of experiments in culture thai low lightintensity is almost certainly an important factorpreventing the development of new sporophytesduring the winter, whereas low water temperatureand short da'y-length are not.

3.3 Phonology

3,31 Seasonal variation in externalappearance and morphology

Seasonal variations in the morphology of S.polyschides sporophy-tea have been studied byNorton and Burrows (1969) at Port Erin, Isle ofMan.

When the new generation of sporphy-tes arosein the spring, the smallest plants that were re-cognisably S, polyschides possessed a round stipe,not yet twisted and the lamina was invariablyentire. Above the prominent holcifast the stipebore a small circular ridge from which the cha-racteristic bulbous structure developed. Theridge produced from its margin 8 or so projectionswhich became the first row of haptera. Duringthe summer the rid expanded both outward anddownward arid further whorls of hapt era developedon its upper surface, It was usually possibleto distinguish the separate whorls until 5 ormore had been produced, By this time -the basalstructure had grown down around the holdfast ob-souring it, much as a bell obscures its clapper.At this stage it greatly resembles the secondaryhol&fast of the adult sporophrte of S. dermatodea,The lowermost, first-formed rows of haptoraelongated and attached themselves to the substratethus supplementing the original holdfast, Inthe late summer and autumn the bell greatly ex-panded laterally arid continued to produce smallprotruberances on its upper surface, This lar,hollow, warty 'bulb' is characteristic of theadult plant, Bulb diameter was often restrictedby the close proximity of adjacent bulbs. Mean-while, the greatly expanded lamina almost in-

FIRM/S83 bulbous Laminaria 3:3

variably became divided into a uusber of digits.The etipc too lthened1 becmo flattened andspirally ttiisied at the bace îthere it iidoned tomerge into the top of the bulb.

The bulb continued to increase in eine fromOctober to December end produced numerous rows ofhaptera, Often adjacent bulbe coaleeced exten-sively so thet the individual plante uere difficultto distinguish. This fact mey have led to theerroneous statement of Barber (1889) that one bulbcould have several stipes. Sometimes, quite alarge plant had only a small rudimentary bulbwhich was fused to a much larger bulb of anotherplant, Often, if the plau rubbed against rocksor other plants, the frill or stipe ,roducedhapterò,-like proliferations from the region ofcontact.

Eventually the top of the bulb, where it joinsthe base of the stipe, became deeply concave, Thestipe progressively widened from Juno to Octoberespecially distally so that it now tapered towardsits base and not towards its tip as before, Theblade also became larger bui, whereas owth during

the summer was much more pronounced in a, longi..tudinal direction giving a lOflL, narrow outlineto the frond, in the autumn lateral expansionkept pace with longitudinal : ow-th and the bladedeveloped a much broader silhouette. The repro-'ductivo frills now developed on the lower regionsof the stipe, They be as flat, lateral ex-pansions of the stipe but subsequently, as a re-sult of differential growth, they became undulated,Sometimes they became prominent structures severalcentimetres in width but often they remained ina rudimentary state.

}To sooner had the plant become adult in ap-pearance and begun to fruit, than decay becameapparent ai the tips of the blade. The rotspread down the thallus thiring the late autumnand winter until eventually both the blade andstipe were lost, The bulb persisted much longerand often overwintered in a fruiting condition,until it also decayed and became detached. fromthe substrate by the following March or April.

Sporophytes which arose during the latesummer and did not become fertile that year over-wintered as intact sporophytes without decaying,At Port Erin these represented only a very smallproportion of the population,

34 FI S83 bulbous Laminaria

FIRM 58 bulbous Laminaria

4 POPULATION

4.1 Structure

4.11 Age composition

Ac S, 2yschides is annual plant thpopulation usually consists largely of plantshioh have arisen at more or less the saeie timo of

year, in the spring. If, however, space becomesavailable new sporophyiea can develop during theuholo of the summer and into the autumn, The ob-servation of labelled sporophytos at Port Brin in-dicated that plants which arose late in the yeardid not fruit timt winter (Norton and Burrows 1969).Such plants overm.ntered intact, without losingtheir stipes from decay as was usually the case,and they became fertile during the following summer,The proportion of these overnnteri aporophytecin the population varied from one locality toanother, On Port Brin breakwater in the summer of

1964 about 10% of the population had overwinterod,In a loose lying community of S. po?'sohidea plantswhich developed in the adjaceut Port Brin bay, theentire population was cast up onto the shore bythe firet storms of winier and therefore no spore-phytes overwinterod, Differences in the propor-tion of the plants which had overwintered intactwere also found in two localities at Lough lue inIreland. In Au,ist 1965 at Carrigsthorna, sea-weed station, less than 1% of the populationappeared to have overwintered and 90% of the plantswere immature, However, in Lough me Rapids, al-most 40% of the population appeared to have over-wintered and 22% was fruiting as early as May,increasing to 76% by August,

4.2 Density

4.21 Average densities of defined areas

Few counts of number of plante of S, ly-schides per unit area have been nde. The presentauthor denuded 24 in2 of Lough lue Rapi' where thespecies was extremely abundant. The averagedensity of 5. 2yschides sporophytes was 7.6/rn2.

4.3 ortality, morbidity

Although sporophytee may be present in thesea throughout the year, individual plante do notusually survive for more than 10 or 11 months,Sporophytes which arise in the spring decay andbecome detached from the substrato by the follow-ing spring, whereas those which do not arise untillater in the summer may survive until the followingsummer,

Sauva:au (1916) considered that the decay ofthe sporophy-tos of S, polyachides in the autumnwas wholly the result of grazing by Patinapellucida, which lives on the fronds, but Nortonand Burrows (1969) concluded that the notion ofPatina, serious as it may be, only aggravated and

accelerated an inherent pettorn of decay,

4.5 Accomp

I-t im siuificnt tha- no m*ter whore the Patinawore aggreatod, deoey alwost invariably bogan atthe tips of tho digue and progressed downwardsuntil first the blade and thon the otipo woregradually lost, For example, on Port Brin brewater in October, 1964, 24% eL' the osaiplo had

rotting blades, but only 2% showed cigno of decayon the stipe. A month later only 4% had rottiblades, bu-t 35% had completely lost their hiedanend their stipes, Since Patina ;as rarely moreabundant at -the tips of -the digits -than elsewhereon the plant, it would seem unlikely that itcould lieve boon -the fundamental cause of the de-cay, This conclusion wac supported by obcerva-tiens of de ing plats which were hardlyaffected by Pati

4.4 !uantitieo standin, oro ofdefined areas

The ave standing crops of S, pyç44aroesed in weight of plants per a for various

localities is shown in Table III. The figuresare somewhat variable, but it is clear that -thequantities recorded in Northern Spain wore muchgrantor -then -thoce found elsewhere, M can beseen from Table IV, in the Spanish material, theleminae of the plants constituted approximatolyhalf the total woih-t of the samples, the bulbend atipo combined constituting the remainder,The same is true of Scottish plants (Table VII),

There is no apparent correlation betweenthe st ding crop of S, yschidee and the typeof substrate.

Table V shows the standing crop ol' S, ,ir-

sohides at thffoi'eut depths in vc.rioua localities,The species does not exhibit a cloar-cu-t patternof weight distribution with depth, This is duo,no doubt, to the complicating effects of competi-tien with other forest-forming leminariana andpossibly different degrees of greci a-t differ

ont depths,

Lug and competing species

Probably the moat important competitor ofS. olycchiden in Britain is Laminaria hyper-boron, bu-t L, saccharine and. L, c1u-oleuca ere

also undoubtedly important competitors in sornoarecs.

Kein (1960) observed ha,t a-t Port Brin -the

upper limit ol' -the Saccorhion cono was relatedto the loTer limit o L, regardlessof th depth at which this was, Only in theabsence of L, perborea did S, yschideareach up -to low water mark, The possible øxis-tenca of some form of competitive inhibitionwas investigated by Norton end Burrows (1969),They denuded au arca in -the L, rborea gone

of all macroscopic sporophytes, The area was,'ecolonioed by S, yochide although not asingle sporophy-te of S, p hides developed

'

FIRM S83 bulbous Laminaria

TABLE III

Mean standing crop of S. ol schides in various localities(recalculated from Grenager 19 4; John 1968; Larkum and Norton,

unpublished.; Walker 1947, 1949, 1949a and 1949b, 1950 and 1955)

Localities

973700447444436425422365334327312287242147138134124122118105

5041

8825484

Depths sampledin metres

Weight in

Spain

Playa de L:. 1 2Isla Onza I - 9LanOans 1 - 8Punta de Alada i - 2Punta Testada i - 8

Norway

Kolçty 5.5 - 10.5Kul5askjarene 5 - 12.5Froj$yene O - 24Sula 0 -14Da].skjaerene 2.5 - 3.5Dagskjemmen 4 - 5.5Nuvaeríy 2,5 - 3.5Preatoy 5 - 6,5Eirtholmene 4,5 - 6.5

Scotland

Hu.ip Holm, Orkney 3.5 - 13North Switha, Orkney 2 - 13Shapinsay, Orkney 2 - 13Bay of Firth, Orkney O - 13Risa, Orkney 2 - 13Linga Holm, Orkney 2 - 13Weddol Sound, Orkney 2 - 11

Sanday Sound, Orkney 2 - 13Little Loch Broom, Ross and Crornarty O - 18Papa Sound, Orkney 2 - 16Kirk Rope Bay, Boy, Orkney 2 - 13Head of Work, Orkney 7 - 8North Para, Orkney 2 - 13Rapness Sound, Orkney 2 - 13Stywick Bny, Sanday, Orkney 2 - 13Euip Nese, Orkney 2 - 18

East Flotta, Orkney 2 - 13Deer Sound, Orkney 2 - 11

Car Ness, Orkney 2 - 11

East Para, Orkney 2 - 13South Flotta, Orkney 2 - 13North Hoxa, Orkney 2 - 11

Ireland

Lough me Rapida, Cork i - 2Whirlpool Point, Lo y me, Cork 3 - 12

Drywt.

267719341615807765

Fresh wt.

300023201733400280240404040

FIRM/583 bulbous Laminaria

TABLE IV

The proportion of the dxr weight/rn2 constituted by the bulb and atipe,and the lamina in varions localities in Northern Spain (from John 1968)

beneath the adjacent forest of L. hyperborea.They concluded that the dim light beneath thecanopy of the forest was insufficient to allow thegrowth of S. polyschides plants,

The faster growth rate of S. polyachides whencompared with L. hyperborea as shown in culture,would enable te sporophyfs to establish them-selves more rapidly at the expense of slower-growing species. When De Valera and Booth (per-sonal communications) independently cleared areasin the Laminaria digitata zone, both areas wererecolonised by S. polyschides and not L, digitata.S, polyachides therefore may be considered to bean opportunist, forming casual populations andcolonising any space that becomes available in thesublittoral region. It has, however, the dis-advantage of being an annual species which must re-establish itself each year whereas its chief com-petitor, L, hyporborea, is perrenial and onceestablished will, in all probability, remain for anumber of years.

The dynamic equilibrium between populationsof S. polyschides and L, hyperborea would help toexplain the fluctuations in the abundance of S.Byschides which occur from year to year in some

localities. For oxmpio in a lagoon at Rhosneigrin Anglesey, North tialos, only one plant was foundin the autumn of 1963 and yet the species wasabundant there at the same time of year in 1965.Gren r (1955), discussing a population in Norway,stated that the very rich community of 1952 haddisappeared almost completely in 1953. Similarly,in Galway, Eire, large populations of S, ychidesappeared and disappeared in consecutive years (DoValera personal communication).

The species which accompany S. pyschidesare the same as those normally found beneath thecanopy of other laminariari algae. In addition,the aporophy-tes are often covered with epiphyticalgae and animals, During the present work atPort Erin arid Loud. me 49 species of algae and89 species of macroscopic animals were recordedon the thallus of S. polyschides. An ecologicalaccount of the epifauna of S, polyschides has boonpublished (Norton 1970a).

Most of the epiphytic species were casualsrather than characteristic members of the epifloraand epifauna. Not a single species was confinedto S. polyachides, but several were much moreabundant on this host than on other algae or on

4:3

Locality Depth Bulbs and Stipes L mae Debris

Punta de Alada 1.8 366 409 32

Playa de Lago (inlet) 1.8 878 572 22

Playa de Lago (channels) 1,8 2047 1718 117

Punta Testada 1.8 466 486 46

3.7 654 546 14

7.3 29 53 O

Las Osas 1.8 593 479 16

3.7 1114 707 O

7.3 1069 851 14

Isla Onza 1.8 2159 1110 o

5.0 910 921 211

8.4 246 231 12

Total weights 10531 8083 484

Total percentages 55.2 42,3 2.5

V

Standing crop of S,

poly

idcT

different dctij in arious locliioa (reca1culaod. from

Gre..r 1964; John 1968; Laki

id iorton, unpubli:

iker 1947, 1949 wid 1949b, t950 and 1955)

Depth

Punta Lae

IslaPro1 ene SulaCulosicj Dak Deer Sound,

Test08a Otìs Onza

rono

jrnon

Orkney

in m-

Car Ness, Shapinsay,

Orkney

Orkney

Orkney

Huip

Rapnesa,,

Holm

Orkney

Orkner

Little

Thirlpool

Loch

Cliff

Broom

Louh Iio,

Ro5

2Cork

Cro:ïrty

1.0

00

0

1.6

998

1088 3269

0O

O357

OO

745

3,7

1214

1821

800

1600

00

O516

96

O482

1440

4.5

-400

5.0

2042

400

5,5

-1600

71

65

235

630

041

485

7.5

82

1934

8800

400

20000

110

392

53

396

128

810

70

8,4

-489

-0

648

o

9,0

2800

-184

680

0335

212

768

0

9,5

400

-

11.0

120

432

65

0176

1340

0

11.5

800

0-

-10

to12,8

00

00

0120

00

LJ co co o o, t-.

Dz7wt.

Fresh wt.

2

Spain

Norway

Scotland

Iroltnd

the surrounding rock0 These were the alGiîTorclia hiucksiae and the animals ulariasp. Oheim onicuiaa Halosydna mnosa,

Nerema Lmneus longmssmrnus Gammarusiocusta, Jassa aloata, Patina pellucida Lacunavmncta9 Gibbula cmnerria1 Astermas rubonsPsammechmnus miliaria, Membrani ora membraxiaceaand Ascid.mella as area0

Mo,rt of the epiphy-tee used S. yschidesmerely as a support and their attachment involvedno penetration of the host0 The epiphyticPoiyzoa were in this category and of the algae,only Ectocarpus siliculosus and Ptilota plumosa

were found to ramify into the host tissue0Even without directly damaging the tissue, how-ever, epiphy-tes may be detrimental to the host.For example, a dense covering of epiphytic algaewould undoubtedly prevent some of the availablelight from reaching the frond and might there-fore impair the host's photosynthetic ability.To some extent the abundance of algal epiphy-teswas controlled by browsing animals such asGibbula cineraria and Patina peilucida. Manyanimals, however, are harmful to the host plantand -the grazing seaurchins Echinus esculentusand Paracentrotus lividus are major factorscontrolling the distribution of S. 2yschidesin some areas,

FIRM/S83 bulbous Laminaria 45

FIRM S8 bulbous Laminaria

5 HARVETI1G

5,1 Methods of Harve

The problems of harvesting S. olyschidesaro the same as those which aro encountered uithother epilithic species inhabiting the sublittoralzou. However, it often forms extensive loose-lying populations on moveablo substratos (Burrows1958). Such plants could be easily and economi-cally collected with a dredge or grapnel. Al-ternatively they could be collected from the driftfor vast numbers of plants from loose-lying popu-lations are uauaily cast up on-to the shore by thefirst storms of winter.

S. polyschides is an annual plant. AfterfruitTng, the sporophrte loses the entire stipeand lamina and they are usually cast up onto theshore in large quantities, They could be col-lected economically from the drift, The bulbswhich persist longer are usually cast up duringMarch and April.

5.2 Harvesting seasons

The spox'ophy-tes are the largest seaweedsfound on the Atlantic coasts of Europe and areextremely fast growing. They achieve their max-imwn size in the late summer. If the plants wereremoved at this time a new generation of sporo-phytes would develop during the autumn. Thus onearea would supply two harvests per year.

All par-te of the sporophy-te including thebasal bulb produce reproductive son. Therefore

only -the bulb need be left to overwinter tó en-sure a supply of spores from which next year'sgeneration of sporophytee may be derived.

5.3 Harvesting areas and depths

Although its distribution is somewhat spora-dic it can be extremely abundant locally, of-tento the exclusion of other lazniriarians, It isparticularly abundant on the south-west coast ofIreland and on the north-east coast of Spain.Both countries already possess an industry har-vesting and utilizing laminanian alve.

Althouöt it can occupy a considerable depthrange, in the absence of other laminarians itforms extensive populations in shallow water up tolow water mark where it can be gathered easily byhand,

5.4 Regrowth on harvested areas

S. po4yechides is an opportunist and if bedsof Laminaria digitata or L, hyperborea are removed(by harvesting for example) they are often re-placed by S. 2yschides. It would therefore bemore economical to utilise the S. polysohideswhich initially replaces the laminarians than towait for the species of Laminaria to re-establishthemselves,

Areas denuded in the spring, summer or autumnwill probably be recolonised immediately, but ifs-tripped during the winter an area will remainbare until the beginning of the growing season ofS, polyschides in the following spring.

S8 bulbous Laminaria 6:1

6 PROTECTION AND MANAGEMENT

6.4 Control of Molo deal features

6.41 Control of predation andcompetition

In roclzy areas colonissioii by S, olyschidesmight be induced by the removal of competing species duruig the sporing season o' S. îolyochides,The colonisation of euch areas tTould be ancouragdby the removal of graelng echinoderìe, Sea-'

urchins can be destroyed un s vsr by divers, providing animale are mostly more ;an 20 rise in dia-.meter and their abundance does at exceed 4/rn2.A relatively cheap alternative nihod for theroutine eradication of sea-urchins is the periodicapplication of CaO (commercial quicklime), Thisinduces tissue loss on contact and sea-urchinswere found to be the organisms most sensitive toi-te effects both in culture and in the sea(Leigh-ton et al,,, 1966). A concentration of0.5 kilm2 resulted in a marked reduction in thesea-urchin population with little effect on other-

animale and a great increase in the amount cflaminarian algae, The easiest method of applying quicklime is to allow it to fall graduallyinto the tiaice of a moving boni, as it passes backand forth over the area to be treated,

6.5 Artificial culture

It should be possb1e to introduce the species into areas here it is noi, at present found,It can groi usil in sheltered areas on unstablebottoms if provided with small pebbles, shellfrasents or possibly submerged ropes for attach--'ment, Such substrates aro unsiutuble for -theattachment of S, 2 achides main cornpeitorsLaminaria arborea end L, ochroleuca,

Sporophytes of S, are easilytransplanted from one locality to another(Nor-ton 1969), Sporing could be induced infertile transplants by allowing the thallus todry out slightly, without overheating, beforesubmergence at the area to be colonised.

FIRM/S83 bulbous J"

7 CEICAL COMPOSILON

7.1 Water content

The uter conton of ope ph,jrtcj of S olfror the coac3to of Prtual je ivon in

Tablo VI, It con itutee on avo'a of theplante uoight,

7,2 anic constituents

The chemical composition of S, chidhas been studied on the coaote of Potual (Mach'.dost a1, 1966g Froao 966) and Scotland (Black1947. Their dza aro eunmarised in Tables VI andVII respectively and ohon that

TABLE VI

The chemical composition of S, polyschides from the coast ofPortugal (recalculated from Machado et cl,? 1966 end Fraoco 1966)

The total cob content ao auch bighoi' thanin other a inoriane althcub the o rent ofnater inoolublo cob to ieilar to that ofother Lanncricloo, It io intoroetin tonoo t h0ï entent of 5.5% lice boon

recorded for ioreocyo tie loutkcana aleo anrnuivl plant,

The ioth.no content uau conoiderably louerthen in the other liniiicriano and tice of theorder found in vllur nodocum,

The potassium levels were high,

Composition Maximum Mean Minimum

Water content (%) 37,7 15,1 6,7gm/100 gm dxr wt,

Total nitrogen 2.8 1.8 1,0Ash 58.8 44.6 27.2Iodine 0,11 0.09 0.01

Crude proteine 17.2 11,4 6.4Fat 0,9 0.3 Trace

mg 100 6:y t,

Ca 2207 1340 897

Mg 1288 642 240

P205 1265 517 254

Fe 303 55,5 3343

Na 6991 5196 3343

K 18800 12218 6576

Na/K 0.7 0,44 0,3

Cellulose 20,3 8.7 4.9Mannitol 15,1 8,0 0,9Lwninarin 5,3 1.1 TraceAlgiriic acid 29,7 21,9 14,6Chlorides in NaCl 37,9 28,1 10,4Sulphates in CaSO4 5,7 3.8 2.5

TAJ3LE VII

The aoaFiona vcrion in the composition of S, al schides fromCullipoo3. Uec Scoiand November 1945 October 194e from Black 1948)

TABLE VIII

The seasonal variation in the composition of S, polyachides from thecoasts of Portugal, March November 1963 (from Ì.Iachado et al., 1966)

% weightfrond stipe whole plant frond atipe frond stipe frond stipe frond stipe

Dry weight 9.94 9,76 '10,0 9,82 7,39 11.03 9.68 10,27 8.89Total ash 47,1 51,0 48,8 41,7 55,0 32,1 42.3 38,9 31,5 37.6 35,1Iodine 0,12 0,12 0,07 0,06 0.09 c,1O 001 0,05 0,13 0,16 0,11

Crude proteins 7,5 5.6 5,0 5,9 3.5 5.9 4.8 4.9 5,4 6,2 5.6Mannitol 4,5 5,8 15,0 22,0 11,9 28.2 23.1 21.7 21,5 16.0 19,5Alginic acid 14,8 15.8 13,1 11,8 14.5 12,9 13,1 14.0 14,0 15,7 15,6Laminarin ¿1,0 1,O 1,O 1,O 1.O 1.O .1.O <1,0 .1,0 .1,0 1,O

Composition%th7wt.

March-.

AprilMay June

July-.

AugustSeptember-.November

Total nitron 2.3 2,0 1,8 1.6 1.7

Ash 42.5 47,4 48,1 44,8 40,5

Crude proteins 13,9 12,3 11.4 9.7 10,5

Fat 0,2 0,4 0,3 0,3 0,3

Cellulose 8,0 7.6 6.7 8,6 12,4

Mannitol 7.6 6.2 8.0 11,5 7,2

Lam marin 1,2 1,0 0,6 0,8 1.9

Alginic acid 23,6 19.3 21,4 22,1 24.0

7;2 FIRM S83 bulbous Laminaria

CompositionNovember June July August September October

FIRM/583 bulbous Laminaria 7:3

7,3 Organic constituents

The organic constituents of S. polyschidosare also given in Table VI.

Seasonal variations in the organic constitu-ents of S. 2yschidos have been studied on thecoasts of Scotland (Black 1948) end Portugal(Machado et al., 1966). Their data arc summa-rised. in Tables VII arid VIII respoctively.

7.31 Carbohydrates

The values of carbohydrates obtained byBlack (1948) arid Machado st a]., (1966) for 5,polyachides were compared with those obtained.from other laminarians from the same localitiesand several points emerged:

Laminarin was present in only very smallamounts.

The mannitol content was high, reaching amerimum value in August and. deoreasing to aminimum in November, It is interesting tonote that an armual plant should build up

such a large reserve of mnnitol. No doubta considerable eiuoun of mannitol would berequired to sustain the rapid grot-rth of thesporophyts in the spring, Before Novcmberhowever, the maniutol lind practically ths'appeared: end it my be that mennutol endhigher synthe,io products jero used. up insporing and maintaining life when photosynthesis had ceased.,

The algunic acid content was somewhat lowerthan that fornid in Laminaria digitata, butwas comparable with the levels recorded forother leiuinariaue,

7,35 Other organic constituents

The biologucl activily of chemical extractsof S. yschides has been tested by Vicites,¿Ireses and Loureiro (1968) using the elongationof Avena colcoptiLso test, The acid fractionwas found to have en Hf of 0.3 to 0.5 and heneutral fracon on Hf of 0,4 to 0,8, The phenolic fraction ethi1ji led varying degrees of stronginhibition on growth,

FIRM 58 bulbous Laninaria

8 UTILIZATION

8.2 ii.i]. fodder

The pecieEi is little used todey for coarner-cial purposes although qucntities cast up ontothe shoro are sometimee collectoci, together uithother laminrians, end made iuto eeatieod meal,

8.3 ura

Saccorhiza polyechidel3 hs furnishedcellent manure for the 1.d (GreviJJ.o 1830 o

8:1

8,4 Industrial products

Forinor].y, S, 2hides as one of the mostwidely used algae in the msnuí'cture of kelp, al'though its use was largely conrined to areas wherelarge quantities tiers regularly thrown up ontothe shores e, in llestern Irelnd in Scotland(Chapman 1950) and in the Isles of Soilly(Groville 183O) It we,c tidoly used for the extraction of iodine end. in the manufacturo of glassend soap (Landsborough 1851),

As it is relatively rich in rnannitol, po-tas-.siusi, and to a lesser extent alginic acid, it mayrepresent an important po-tntial source of thesesubstances,

FIRM S83 bulbous Laminaria :1

9 RFEREffC

Agardh, C.A,, Species algarum, Vol.1 (1):1-1681820

Barber, C,A,, On the structure and development of the bulb in Laminaria bulbosa Lamour. Ann.

1889 Bot,, 3:41-64

Batters, E.A,L., A catalogue of the British marine algae. J.Bot., Lond., 40(Suppl.):107 p.1902

Beauvois, A.M,F.J. Palisot de., Flore d'Oware et de Benin. Paris, Vol.1:1-981805

Bell6n, L., Atlantic seaweeds of the Malagan coast, Proc.int.Soaweed Symp., 1:5

1953

Bellán-Uriarte, L,, Nota sobre una Saccorhiza bulbosa (Huds,) La Pyl. de Melilla (Mediterraneo1925 Occidental), Nuova Notarisia, 1925:217-21

Black, W.A.P., The seasonal variation in chemical constitution of some of the sublittoral sea-1948 weeds common to Scotland. 3, Laminaria saccharina and Saccorhiza bulbosa. J.Soc.

chem.Ind., Lond., 67:165-8

Bornet, E., Les algues de P.IÇA, Sóhousboe. Mem.Soc.natn.Sci.nat.math,Chorbour, 28:165-3761892

Bory de Saint Vincent, J.B,G,M., Laminaire, In Dictionnaire classique d'Histoire Naturelle,1826 Paris, Vol.9:187-95

Burrows, E.M., Sublittoral algal population in Port Erin Bay, Isle of Man. J.mar.biol,Ass.U.K.,

1958 37:687-703

Chapman, V.3., Seaweeds and their uses. London, 287 p.1950

Crouaii, P.L, and H,M, Crouan, Algues marines du Finistre, Vol.11852

Dangeard, D., Les algues marines de la c6te occidentale du Maroc. Botaniste, 34:89..185

1949

Decaisne, J,, Essai sur une classification des algues et des polypiers calcifres do Lamouroux.1842 Annls Sci.nat.(Bot,), (2), 17:297-380

de Lamark, J.B, and A.P. de Candolle, Flore française, ou descriptions succinctes de toutes les1805 plantes qui croissent naturellement en France, Vol.2:600 p.

Evans, L.V., Cy-tological Studies in the Laxninariales. Ann.Bot,, 29:541-621965

Feldmann, J., La Floro marine de l'Afrique du Nord. C.r.somm,Seanc,Soc.Bio ogr., 243:103-81951

Frazao, S., Doseamento do jodo nas algas (nota tecnica), Estud.Biol,Inst,nac.Invest.ìnd.,1966 3:181-91

Funk, G., Die Algenvegetation des Golfes von Neapel, nach neuen b'kologischen Untersuchungen.

1927 Pubbl.Staz.zool.Napoli, 7(Suppl.):1-507

Gayral, P., Algues de la C8te Atlantique Marocaine, Rabat, 523 p,1958

Grenager, B,, Kvantitative underskeleer av tareforekomster i Sr - Heloland 1952 cg 1953.1955 Rep.Norw.Inst.Seaweed Ree,, 7:1-53

9:2 PIRM/S83 bulbous Laminaria

Grenager, B., Kvantitative undors1kelser av -tang-ag -tareforekomster i Nord-Frya herved 1954 cg1964 sund herved 1956, Re ,Nori,Inat.Seaweed Res., 28:1-53

Greville, RK., Al

1830e Britannaicae. Edinburgh, 218 p,

Hudson, W,, Flora Anglica. London, vol.2:397-6901778

John, D.M., Studies on littoral and sublittoral ecosystems. Thesis, University of Durham1968

Kam, J.M., Direct observations on some Manx sublittoral algae. J.mar.biol,Ass. U.K., 39(3):609-301960

The biology of Laminaria hy-perborea, 5. Comparison with early stages of competitors.1969 J.mar.biol.Ass. U.K., 49(2):455-73

Kam, J,M. and N.S. Jones, Algal colonization after removal of Echinus. Proc.int.Seaweed Syinp.,1966 8:139-40

KU-tzing, F.T,, Phycologia Generalis oder Anatomie, Physiologie und Sys-temkunde der Tange. Leipzig,1843 458 p.

Lamouroux, J.V,, Essai sur les genres de la famille des Thallassiophytes non artioules. Mn-ils Mus.

1813 Hist.nat.Paris, 20:21-47

Landsborough, D., A popular history of British seaweeds, London, 400 p.1851

Leighton, D,L,, L.G, Jones and W,J, North, Ecological relationships between giant kelp and sea-urchins1966 in Southern California. Proc,int.Seaweed Symp., 5:141-53

Lewis, J.R,, The ecology of rocky shores. London, English University Press, 323 p,1964

Lighifoot, J., Flora Scotica, London, vol.2:531-11511777

McAllister, H.A., T,A. Nor-ton and E. Conway, A preliminary list of sub-littoral algae from the West1967 of Scotland, ,phycol,Bull., 3(2):174-84

Machado, B,R., e-t al,, Composicac global, mineral e glicidica, Estud.Biol.Ins-t.nac.Invest.ind,, (3):1966 1-179

Meunier, R. and J, Picard, Notes biologiques propos d'un voyage d'&tude sur les c6tes de Sicile.1953 Arinis Inst.Oceanogr., Monaco, 28:164-87

Nor-ton, T.A,, Growth form and environment in Saccorhiza polyschides. J.mar.biol.Ass.U.K., 49(4):1969 1025-45

The development in culture of the laminariaii alga Saccorhiza derma-todea. Phycologia1970

An ecological study of the fauna inhabiting the sublittoral marine alga Saccorhiza1970a polyschides. Hydrobiologia

Norton, T,A, and E.M, Burrows, Studios on marine algae of the British Isles. 7. Saccorhiza polyschides1969 (Lightf.) Batt. Br.phycol.J., 4:19-53

The environmental control of the seasonal behaviour of Saccorhiza polyschides (Lightf.)1969a Bat-t. Proc,int,Seaweed Symp., 6:287-96

Norton, T.A, and G.R, South, An experimental assessment of the influence of salinity on the distribu-1969 tion of two laminarian algae. Oikos, 20:320-6

Phillips, R.W., Note on Sa000rhiza bulbosa J.G: A.G, and Alaria esoulenta Grey. Ann.Bot., 10:96-71896

Prints, H., Die Algenvegetation des Trondhjemsfjordes, Skr.norske Vidensk-Akad,, 5:1-2731926

Provasoli, L., J.J.A. McLaughlin and M,R. Droop, The development of artificial media for marine algae.1957 Aroh.Mikrobiol., 25:392-428

Pylaie, Bachelot de la, A.J.M., Flore de l'île de Terre-veuve et des fies St. Pierro-et-Miqielon1829 Paris, 128 p.

Sauvageau, C., Sur le dveloppement et la biologie d'une Laminaire (Saccorhiza bulbosa). C.r.hebd,1915 Seanc.Acad.Sci., Paris, 160:445-8

Sur les variations biologiques d'une Laminaire (Saccorhiza bulbosa), C,r.hebd,Seanc.1916 Acad.Sci., Paris. 163:396-8

Recherches sur les Laminaires des c8tes de Franco, Mem.Acad.Sci., Paris, 56:233 p.1918

Schreiber, E., Untersuchungen tXber Par-thenagenesis, Geschlechtsbestimm-ung und Bastardierungavenngen1930 bei Lazninarien. Planta, 12:331-53

Seoane-Camba, J., Las laminarias de Espa.a y su distribucion. Publnes tec.Jta Estud.Pesca, (5):425-361966

Spence, M., Laminariaceae of Orkney: their ecolor and economics. J.Bot.,Lond,, 56:281-51918

Stackhouse, J,, Tentamen marino - cryptogamicum. Mern.Soo.imp.nat.Moscow, 2:50-971809

Svendaen, P., Some observations on Saccorhiza olyschides (Lightf.) Batt. (Phaeophyceae,) Sarsia,1962 7:11-3

Sykes, M.G., Anatomy and histolor of Macrocystis pyrifera and Laminaria sacoharina. Ann.Bot.,1908 22:291-325

Vieitez, E., L. Areses aM M. Loureido, Actividad biologica de fracciones de extractos de Himanthalia1968 elongata, Gigartina stellata y Saccox'hiza bulbosa. Abstract presented to 6th International

Seaweed Symposium

Walker, F.T., Sublittoral seaweed survey. Pt,1. Development of the View Box - Spring Grab technique1947 for sublittoral weed survey, Pt, 2. Survey of Orkney, Scapa Flow. Pt.3. Survey of Orkney,

Bay of Fir-th, J.Ecol,, 35:166-85

Sublittoral seaweed survey. Pt.12. Car Ness - Head of Work, Orkney. Rep.Scot.Seaweed1949 Res.Ass., (118):1-5

Sublittoral seaweed survey. Pt.13, Stywick Bay, Sanclay, Orkney. Rep.Scot.Seaweed Res.1949a Ass., (119):1-2

Sublittoral seaweed survey. Pt.14. Orkney Mainland, Rep.Scot.Seaweed Res,Ass., (125):1949b 1-5

Sublittoral seaweed survey of the Orkney Islands. J.ecol., 38:139-651950

A sublittoral survey of the Laminariaceae of Little Loch Broom. Trans.Proc.bot.Soc.1955 Edinb., 36(4):305-8

This is one of a series of documents issued by FAO, CSIRO and USFWS concerning species and stocks ofaquatic organisms of present or potential economic interest. The primary purpose of this series is to makeexisting information readily available to fishery scientists according to a standard pattern, and by so doingalso to draw attention to gaps in knowledge. lt is hoped that synopses in the series will be useful to otherscientists initiating investigations of the species concerned or of related ones, as a means of exchange ofknowledge among those already working on the species, and as the basis for comparative study of fisheriesresoL!rces. They will be brought up to date from time to time as further information becomes available eitheras revisions of the entire document or their specific chapters.

The relevant series of documents are:

FAO Fisheries Synopsis No.replacing, as from 1.1.63 FAO FisheriesBiology Synopsis No.

CSIRO Fisheries Synopsis No.

and

USFWS FAO Fisheries Synopsis No.

Synopses in these series are compiled according to a standard outline described in FIb/Si Rev. 1 (1965).

FAO, CSIRO and USFWS are working to secure the cooperation of other organizations and of individual scien-tists in drafting synopses on species about which they have knowledge, and welcome offers of help in this task.Additions and corrections to synopses already issued will also be most welcome. Comments including sugges-tions for the expansion of the outline and requests for information should be addressed to the coordinatorsand editors of the issuing organizations.

FAO:Fishery Resources DivisionMarine Biology and Environment BranchFood and Agriculture Organizationof the United NationsVia delle Terme di Caracalla00100 Rome, Italy

USFWS:Department of the InteriorBureau of Commercial FisheriesOffice of Scientific PublicationsBuilding 67, U.S. Naval Air StationSeattle, Washington 98115, U.S.A.

SYNOPSIS OF FISHERIES BIOLOGICAL DATA

CSIRO:Scientific EditorCSIRO Division of Fisheries and OceanographyBox 21Cronulla, N.S.W.2230 Australia

The following synopses in this series have been issued since January 1969:

BCF/S40 Synopsis of biological data on the Pacific mackerel Scomber japonicus Houttuyn(Northeast Pacific)

FRi/S30 Synopsis of biological data on the pike Esox lucius (Linnaeus) 1758Rev. i

DFOIS3 Synopsis of biological data on the tiger prawn Penaeus esculentus HasweU,1879

FRm/S43 Synopsis of biological data on the anchoveta Cetengraulis mysticetus Günther,1866

FRh/S35 Synopsis of biological data on West African croakers Pseudotollthus typus,Rev. 1 P. senega/ensis and P. elongatus

BCF/S42 Synopsis of biological data on the Atlantic menhaden, Brevoortia tyrannus

FRm/S78 Synopsis of biological data on smelt Osmerus spar/anus (Linnaeus) 1758

FIRI/S80 Synopsis of biological data on the eel Anguilla anguilla (Linnaeus) 1758 (Provi-sional version)

DFOIS4 Synopsis of biological data on the rainbow prawn, Parapenaeopsis scuiptiis(Heller, 1862)

BCF/S4 Synopsis of biological data on chum salmon Oncorhynchus keta

DFO/S5 Synopsis of biological data on the school prawn Metapenaeus macleayi(Haswell, 1879)

FIRIIS8O Synopsis of biological data on the eel Anguilla anguilla (Linnaeus) 1758Rev. 1

FIRM/S82 Synopsis of biological data on North Atlantic sandeels of the genus Ammodytes(A. tobianus, A. dubius, A. anwricanus and A. marinus)

FIRM/S83 Synopsis of biological data on Saccorhiza polyschides

FR/S

FB/S

D FO/S

BCF/S

Consolidated lists of species or groups covered by synopses issued to date or in preparation will be issuedfrom time to time. Requests for copies of synopses should be addressed to the issuing organization.

February 1969

May 1969

July 1969

October 1969

November 1969

November 1969

December 1969

April 1970

1970

July 1970

1970

October 1970

November 1970

November 1970

Ml/A9075/I 2.70/E/I /850