Distribution of Some

Shallow-Water

Foraminifera in the

Gulf of Mexico By ORVILLE L. BANDY

A SHORTER CONTRIBUTION TO GENERAL GEOLOGY

GEOLOGICAL SURVEY PROFESSIONAL PAPER 254-F

UNITED STATES GOVERNMENT PRINTING OFFICE, WASHINGTON : .1954

UNITED STATES DEPARTMENT OF THE INTERIOR

Dou~las McKay, Secretary

GEOLOGICAL SURVEY

W. E. Wrather, Director

For sale by the Superintendent of Documents, U. S. Government Printing Office Washington 25, D. C. -Price $1.00 (paper cover)

CONTENTS

Page

Abstract___________________________________________ 125 Introduction_______________________________________ 125 Previouswork______________________________________ 125

Method of studY-----------~------------------------ 126 Faunal analysis_____________________________________ 126

General features________________________________ 126 Zonation_______________________________________ 127

Zone 1------------------------------------ 132 Zone 2------------------------------------ 134 Zone3____________________________________ 134

Conclusions________________________________________ 135 Annotated synonymies_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 135 Bibliogr~phy_______________________________________ 139 Index_____________________________________________ 141

ILLUSTRATIONS

Page

PLATE 27. Contour map of Gulf of Mexico between Sabine Pass, Tex., and Grand Chenier, La., showing bottom-sample locations ____________________________________________________________________ ~ _____ - -- _- -·------ in pocket

28-31. Recent Foraminifera, Gulf of Mexico __________________________________________________________ Following index FIGURE 5. Composite frequency distribution of the significant Foraminifera __________________________ ----------------- 127

6. Frequency distribution of the more significant Foraminifera of traverse 1 __________ -- _- _-------------------- 128 7. Frequency distribution of the more significant Foraminifera of traverse 2 _________________ ------------------ 129 8. Frequency distribution of the more significant Foraminifera of traverse 3 _________________ - ~---------------- 130 9. Percentages of Foraminifera in sediment, plotted with number of species for traverse 2 ___ -------------------- 131

10. Generalized bottom-temperature curves, showing seasonal variation ________________ - ___ -------------------- 131 11. Frequency distribution of the Foraminifera of traverse!___________________________________________________ 132 12. Frequency distribution of the Foraminifera of traverse 2-------------------------------------------------- 133 13. Frequency distribution of the Foraminifera of traverse 3 _____ ·--------------------------------------------- 133

III

A SHORTER CONTRIBUTION TO · GENERAL GEOLOGY

DISTRIBUTION OF SOME SHALLOW-WATER FORAMINIFERA IN THE GULF OF MEXICO

By ORVILLE L. BANDY*

ABSTRACT

This is a detailed study of the distribution of Foraminifera between depths of 27 and 130 feet in the Gulf of Mexico between Sabine Pass, Texas, and Grand Cheniere, Louisiana. The area extends about 75 miles off-shore and is about 50 miles wide. The frequency distribution of the species of Foraminifera is plotted against changes in depth, temperature, chlorinity and the median grain size of the sediments. Within the very restricted depth limits of the investigation, there is a marked faunal zonation making it possible to establish bathymetric zones of 30-55, 55-75, and 75-130 feet, and to predict positions even within these intervals.

The seasonal bottom-temperature range is vastly greater than the variation along the whole profile, indicating that the species involved possess considerable tolerance toward temperature variation. Temperature is therefore probably of little or no importance in explaining the faunal differentiation within the area.

Chlorinity appears to play an important role in the near-shore environment. The species of Streblus discussed in this paper were found to be mostly limited to brackish water. Three spe­cies of the genus Elphidium were found to be abundant in waters of both low and normal chlorinity, however, a fourth species was noted only in areas of normal chlorinity. Diversity of adapta­tions within a genus and even within a species is to be expected and this suggests that although Streblus proved to be especially well developed in waters of low chlorinity, there may well be related species that are characteristic of other conditions.

The bottom prominences were found to support a population of Asterigerina car'fnata d'Orbigny, and other characteristic spe­cies. The weight percentages of Foraminifera in the sediment and the numbers of species were found to increase away from shore. Thera is no apparent correlation between the median grain size and faunal trends.

INTRODUCTION

This paper records the distribution of some shallow­water Foraminifera in the northern part of the Gulf of Mexico and attempts to interpret the ecologic conditions controlling distribution. The percentage-abundance distribution of the foraminifers is plotted against changes in depth, temperature, chloride content, and median grain-size of the sediments. The Foraminifera were collected by Messrs. J. D. Frautschy and H. R. Joesting as a part of a reconnaissance gravity survey in the Gulf of Mexico for the U. S. Geological Survey in cooperation with the Office of Naval Research. The investigation·s were carried out on the U." S. Navy re­search vessel Mentor, operated under contract by Woods Hole Oceanographic Institution. The area surveyed

•Department of Geology, University of Southern ,California.

extends seaward about 75 miles from the shore of the Gulf of Mexico between Sabine Pass, Texas, and Grand Cheniere, Louisiana. One of the objectives of the survey was to obtain information concerning the bot­tom .sediments, and the following analysis of the foraminiferal elements is one phase of that objective.

As indicated on the preliminary map by Joesting and Frautschy (194 7), the initial base line of targets for each of the three lines of stations was located by transit triangulation from U. S. Coast and Geodetic Survey triangulation stations on shore. The stations of the survey were then located by triangulation, using 3 centimeter radar and radar-reflector targets mounted on buoys. The maximum uncorrected longitude errors were not more than 2 miles and the corresponding latitude errors were not in excess o{ about one-quarter mile. The stations are located in three north-south traverses that are designated 1, 2, and 3 respectively from west to east (pl. 27). In addition, several samples were collected from intermediate points along the southern edge of the area~ thereby joining the outer ends of the north-south lines of traverse.

The samples and data used in making up the curves for chlorinity, depth and median grain sizes were sup­plied by Mr. J. D. Frautschy, Scripps Institution of Oceanography. Dr. F. B. Phleger and Miss F. L. Parker of the same institution permitted the author to consult the taxonomy of an unpublished paper covering much of the Gulf of Mexico. The bottom-temperature data were obtained from Mr. Frederick C. Fuglister, Woods Hole Oceanographic Institution, Woods Hole, Massachusetts. The writer has attempted to present all of the significant results graphically and in this he was aided materially by the suggestions of Dr. K. 0. Emery, University of Southern California. The work was done under the supervision of Dr. H. R. Joesting, Chief of the Geophysics Branch, U. S. Geological Survey.

PREVIOUS WORK

Studies of the Foraminifera of the Gulf of Mexico may be divided into two groups, those which are pri­marily taxonomic and those which emphasize distribu­tion patterns and ecologic conditions. The first cate­gory includes the well known works of d'Orbigny (1939), Brady (1884), Cushman (1921, 1922, 1926),

125

126 SHORTER CONTRIBUTIONS TO GENERAL GEOLOGY

and Kornfeld (1931). Although these monographs are mainly of a taxonomic nature, they contain depth data from which some distributional trends and tend­encies may be determined. More recent taxonomic papers include those of Acosta (1940), and Lalicker and Bermudez (1941).

Again, although there are depth data to be found in these papers, there is little information about the rela­tive importance of the individual occurrences. Papers emphasizing the patterns of distribution and ecologic conditions include those of Vaughan (1918), Lowman (1949), and Phleger and Parker (1951). Vaughan's study is primarily an analysis of the bottom sediments but he includes lists of Foraminifera occurring at differ­ent stations and the characteristics of the ·environ­ments. Lowman's paper is the first to attempt a graphic representation of the frequency distribllt1'ln of Foraminifera from shore to deep water. He used categories broader than species and varieties, thus providing an excellent perspective of the general ranges and dependability of the genera and families. Phleger and Parker have completed a study that contributes

- much detailed information concerning the ranges of species and varieties of the foraminiferal population offshore. The present study in like manner deals with the Foran1inifera of the nearshore area.

An excellent bibliography of publications dealing with the Gulf of Mexico generally by Geyer (1950) includes references to many papers dealing with ecology of organisms other than Foraminifera.

METHOD OF STUDY

Frequency counts of 160 samples were used as a basis for this investigation. The samples of traverse 2 were weighed before disaggregation and the percent­ages of Foraminifera in the sediment were computed. Although the samples of the other two profiles were not weighed, a roughly uniform quantity of each was selected. The material was washed on 150 mesh screens (0.105 mm) and the residue was then dried and treated with carbon tetrachloride to concentrate the Foramini­fera by flotation. Some broken tests and specimens belonging to a few of the larger genera such as Praesorites did not float readily and had to be decanted from the residue. This last procedure was quite effective, for in the sediment-carbon tetrachloride mixture the Foraminifera are buoyed up much more than the sedi­ment and can be decanted and raked out easily. Ex­amination of the residues revealed fairly clean separa­tion.

In making counts, a foraminiferal sample was split evenly a number of times, until a fraction was obtained that could be accommodated on one counting slide. In the beginning, test counts were made of the various size fractions to ascertain the percentage variation in the qifferent fractions. The largest count was more than

1000 specimens, and it was found to differ from the small counts of about 100 specimens mainly in the num­ber of rare species revealed. For this reason it was decided that counts of 200 to 500 specimens would pro­vide sufficiently accurate results. In a very few sam­ples fewer than 200 specimens were counted, and then only because specimens were rare.

The percentage method was used be<_;ause it accu­rately reveals the relative importance of the various species and varieties in different samples and permits more ready comparisons with other studies of this kind. The percentage method brings out gradational changes more accurately than categories such as rare, common and abundant. Where the faunas are fairly large, the criticism of Said (1950) that the percentage method fails to provide a basis for correlation of the numbers of specimens in different samples is largely elimin'ated. As may be observed in the work of Phleger (1942), Parker (1948), Lowman (1949), and in the charts herein, the advantages of the percentage method lie in the rela­tive ease of zone determination and in correlating gra­dational changes of faunas with changes' in the physical environment.

FAUNAL ANALYSIS

GENERAL FEATURES

The area involved ranges in depth from about 25 ft near shore to approximately 130 ft at the outer edge. As may be seen on plate 27, the bottom is not smoothly sloping but is very irregular so that the three profiles exhibit several topographic highs, possibly salt dome features. Stations near each other geographically and bathymetrically have been averaged together where they seem to present identical faunal associations.

Because some of the stations were grouped together on the maps, it wasn't feasible to locate the stations and grouped stations according to the true horizontal scale, hence the stations are spaced equidistantly. This roughly approximates the proper horizontal spacing, inasmuch as the samples were collected from nearly equally spaced stations.

In the frequency counts of the species of the three traverses (figs. 11-13), it became apparent almost at. once that about 8 to 15 species made up more than 90 percent of the fauna at any one station. It became equally apparent that there were three general classes of variation, viz. general trends such as that exhibited by Streblus and Planulina ornata (d'Orbigny), unusual faunas on topographic highs such as that at station 8,. in figure 6, and sporadic occurrences of many species .. The more abundant and diagnostic forms compared with the changes in the physical environment, showed little correlation excepting with depth and chlorinity (figs. 6-8). In. such analyses there are many fluctua­tions and irregularities that are confusing; however, by making a composite picture of the frequency distri-

SHALLOW-WATER FORAMINIFERA IN THE GULF OF MEXICO 127

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TOPOGRAPHIC HIGHS

FIOURE 5. Composite frequenry distribution of the significant Foraminifera plotted with changes in physical environment.

bution (figure 5, top) in the absence ofthe complicating factors associated with slope reversals, the frequency distribution smoothed out. A comparison of the generalized composite frequency distribution with that on the topographic highs (figure 5, bottom) shows a striking contrast, one which is possibly explained by less turbidity on the bottom highs.

It was found that the weight percentages of Foram­inifera in the sediment increased erratically from the near-shore ends of the traverses outward, a condition probably produced by the dilution of foraminiferal elements by sediment nearer shore (fig. 9). The num­ber of species near-shore was found to be generally about half the number making up the faunas of the stations near the outer ends of the traverses (fig. 6). This last is to be expected with the less turbid condi­tions and the normal chlorinity of the outer zone:

As may be seen in figures 5-8, the bottom tempera .. tures taken when the samples were collected have a range of less than 5 degrees whereas the annual varia­tion shows an annual average range of about 20 degrees

for both the outer and inner portions of the area inves­tigated (fig. 10). Therefore, species having considerable tolerance toward changes in temperature are character­istic of the faunas studied. The correlation of growth periods with times of maximum differences between the bottom temperature near-shore and off-shore may prove to be significant for some of the species but evidence of this kind is yet to be obtained. The fluctuations in grain size do not seem to correlate with the faunal trends and therefore appear to be non-significant.

ZONATION

In several bathymetric studies of the distribution patterns of the tests of Recent Foraminifera, well­defined zones have been recognized. Natland (1933) established five zones in his work off the southern California coast, Parker found four zones in her study of the Atlantic coast (1948), and Lowman recognized 12 faunal associations in his Gulf coastal work(1949). The present study is a detailed examination of an area which is roughly equivalent in depth to zone 2 of N atland,,

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SHALLOW-WATER FORAMINIFERA IN THE GULF OF MEXICO 131

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132 SHORTER CONTRIBUTIONS TO GENERAL GEOLOGY

parts of zones 1 and 2 of Parker, and faunal associations 6 and 7 of Lowman. For discussion it is convenient to divide the traverses into 3 depth zones; these are of course phases of the more generalized zones of others, and only a means of analysis of the problem at hand. The general zonation with its gradational nature is marked (fig. 5). The general subdivisions, however, are clear, and these are tabulated and discussed below.

Relative abundance of species of Foraminifera in bottom samples taken at different depths

[Abundance of each species is expressed as the range of the percentage it makes up in i . , . . ' the wbole fauna.]

Abundance in zones indicated

2 3

(3o-55 ft.) (55-75ft.) (75-130 ft.)

Streblus beccarii sobrinus, S. b. tepidus, and S. rolshauseni______ 40+ 20-40

Elphidium discoidale, E. gunteri galvestonense, and E. poeyanum _ _ 25 + 20-30

Hanzawaia strattoni_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 10-45 Discorbis jloridanus______________ ________ 1-14 Planulina ornata________________________ 0-1 Globigerinoides rubra _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ ______ _ Cancris sagra __________________________________ _ Eponides antillarum _________________ · ____________ _

ZONE 1, 3Q-55 FEET

0-15

10-35 10-40

1-10 2-18 2-10 0-5 0-5

It will be noted that there are many fluctuations in the frequency curves for the faunal indices in zone 1, and no single species is a dependable criterion; however, by setting the minimum total percentage of 60 percent for all of the species of the two genera listed above, allowance is made for exceptions such as that seen at station 126 in figure 8. At this station the cumulative percentage of the indices listed above is 73 whereas that of Streblus alone is only 12 percent. Another type of exception is that seen on bottom highs 1 and 2 (fig. 6) where the cumulative values are 25 and 38 percent respectively. Asterigerina carinata d'Orbigny appears and Hanzawaia strattoni (Applin) becomes very abun­dant, a condition typical of the frequency distribution in zone 2 (55-75 feet). The two occurrences are difficult to separate, about the only differences being in the probability of encountering Planulina ornata (d'Orbigny) and other deeper water species in zone 2 whereas they are characteristically absent on the shallow water bottom highs. The deeper water bottom highs usually show a much greater frequency of Asteri­gerina carinata d'Orbigny and the appearance of Praesorites orbitolitoides Hofker.

In the histogram charts (figs. 11-13) the two varieties of Streblus beccarii (Linne) are lumped together be­cause their ranges are approximately identical and because of their similarity. In the composite charts, FIGURE 11. Frequency distribution of the Foraminifera of traverse 1.

SHALLOW-WATER FORAM~NIFERA IN THE GULF OF MEXICO 133

~ ~ ~~t ~ ~.

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FIGURE 12. Frequency distribution of the Foraminifera of traverse 2. FIGURE 13. Frequency distribution of the Foraminifera of traverse 3.

134 SHORTER CONTRIBUTIONS TO GENERAL GEOLOGY

all of the members of the genus Streblus are lumped to­gether, again because of their similar ranges. Of the ecologic data available, there are two variables, depth and chloride content. According to Lowman, Streblus and Elphidium are dominant where the chlorinity is from 5 to 15 (1949, p. 1953). In the data herein, the chlorinity ranges from about 12 near the inner ends of the lines of traverse· to about 19.8. Streblus and its various species were found to be most abundant where the chlorinity was less than 19 (figs. 5-8) and only com­mon to rare where the chlorinity was 19 or above. Along the California coast, S. beccarii (Linne) and its variants are reported from only the lagoonal areas in shallow brackish water (Natland, 1933). Hedberg (1934) also noted this in Venezuela. A correlative factor is turbidity, for the waters of the Gulf were quite turbid out to about the 18 mile light when the samples were collected in August and September, 1947 (oral com­munication, J.D. Frautschy), a condition produced by the influx of mud-laden fresh water into the coastal waters of this area. This too, explains the low chlorin­ity near shore. Streblus rolshauseni (Cushman and Bermudez) drops to less than 1 percent beyond the depth of 80 feet; however, as much as 10 percent (in one case 14 percent) of the faunas of the outer zone may be made up of the varieties of Streblus beccarii (Linne). In summary, the species of Streblus encountered are apparently suited to maximum development in brack­ish waters but may tolerate shallow waters of near normal chlorinity.

The three species of Elpkidium listed for this zone were lumped together for the composite analyses be­cause their individual distribution patterns, as pre­sented in figures 8-10, are nearly identical. These species are common to abundant in all of the samples, indicating that their ranges of tolerance exceed the ecologic variation found in the area of this study. The ability of this genus to tolerate considerable ranges of environmental change was brought out by Myers (1943) in his study of E. crispum (Linne). He found this species to be one of very few that thrives both in the intertidal and sublittoral zones. From the work of Lowman (1949, p. 1953) it is evident that Elphidium cg,n tolerate moderately brackish water and that it thrives in the broad inner neritic zone. Its range of tolerance, however, exceeds that of Streblus beccarii (Linne) as may be seen in figure 5, for it is abundant throughout the area of this study. One exception to the range of this genus is E . .fimbriatulum (Cushman). This species, which is rare, is restricted to samples ob­tained beyond the brackish water area and a few samples from some of the prominences in the shallower water.

Discorbis fioridanus Cushman is absent from the shallower parts of the area studied, but is present at depths of 40 to 50 feet and is significant therefore as

indicating the deeper part of this zone. Quinquelocu­lina lamarckiana d'Orbigny, a rather uniformly distrib­uted species, exhibits a few significant deviations. There is a rather marked percentage increase of this form on the topographic highs in shallow water (fig. 5) and at stations 83 and 84 (fig. 7). At stations 83 and 84 a slight reversal in slope places this occurrence also in the bottom-high category.

ZONE 2, 55-75 FEET

This zone is transitional between the Streblus­Elphidium and the Planulina ornata zones (table, p. 132). It is characterized bytheabundance of Hanzawaia strattoni (Applin) and a-very low percentage or the com­plete absence of the deeper water form, Planulina ornata. As indicated in figure 5, the chlorinity is still slightly lower than that farther out, perhaps accounting for additional species appearing only gradually with increasing depth. It is also likely that turbid bottom conditions help determine the character and quantity of the benthonic fauna by reducing the translucency of the water and consequently the abundance of plant life.

The counts of Hanzawaia strattoni (Applin) include a very few specimens of H. concentrica (Cushman) which differs from H. strattoni in possessing a flat dorsal side and angled edge (Cuslunan, 1918, p. 64). As mentioned in the discussion for Zone 1, there may be a marked increase in this form on shallow bottom highs but in these cases, it is associated with Asterigerina carinata d'Orbigny and other rarer forms found in slightly deeper water (see station 8, fig. 11).

In general, this zone differs from Zone 1 in that Hanzawaia strattoni is more abundant than Streblus, and a few specimens of Planulina ornata and Globigeri­noides rubra may be expected (see fig. 5).

ZONE 3, 75-130 FEET

Of the species listed as characteristic of this zone (table, p. 132) Planulinia ornata(d' Orbigny) is most significant in determining approximate positions within the zone. For example, the frequency of this species increases from about 2 to 10 percent between depths of 75 and 100 feet and is in excess of 10 percent below 100 feet. No known ecologic factor is correlated with the appearance and progressive percentage increase of this species, but may be related to the distribution of plant life and food supply.

Discorbis floridanus Cushman seems to be most abundant at depths of 50 to 100 feet. The upper limits of distribution fall in the shallower zones, and the lower limits, are at about 100 feet.

The gradual appearance of many species in pro­gressively deeper water is marked as may be seen in figures 9, and 11-13. Some of these are rare, sporadi­cally distributed and are seemingly of little importance in this study. The distribution of some others are

SHALLOW-WATER FORAMINIFERA IN THE GULF OF MEXICO 135

important but are omitted from the composite charts to a void over-crowding and confusion; however, they are shown in figures 11-13. In this last group are species such as Cancris sagra (d'Orbigny) and Eponides antil­larum (d'Orbigny) whose abundance increases rapidly near .the outer ends of the. traverses.

The faunas of the prominences present an interesting digression from the general trends as may be seen by comparing the composite charts in figures 5-8. The prominences, whether in deep or shallow water, are characterized by the presence of Asterigerina carinata d'Orbigny; however, there is a much greater abundance of this species on the prominences lying at depths of 60 to 130 feet. Other species characteristic of these deeper-water prominences include Praesorites orbitoli­toides Hofker and Textularia candeiana d'Orbigny which, although not restricted to the prominences, are more abundant there than elsewhere. With the excep­tion of area no. 5, there seems to be a marked drop in the frequency of Hanzawaia strattoni (Applin) on the deep-water prominences whereas the percentages of Elphidium remain about the same.

On prominence 4 in traverse 2, a sharp increase in the frequency of Textularia candeiana d'Orbigny is as-

. sociated with a marked increase in median grain size. This occurrence coincides with the presence of coarse sand particles usable in the building of the test, but there is no corresponding increase near prominence 5 in traverse 3, where the median grain size. shows a marked increase with no significant change in the frequency of T. candeiana. With the one exception at prominence 4, there seems to be no dependable cor­relation between grain size and frequency distribution of the faunal elements studied.

CONCLUSIONS

1.-Within a depth range of about 100 feet, it is possible to establish three rather well defined faunal zones that parallel the coast. The zonation is grada­tional, enabling one to predict positions within the general zones.

2.-The seasonal range of bottom temperatures of about 20° F is much greater than the range of readings

·taken when the samples were collected. This would seem to rule out temperature as a determining factor in faunal differentiation within the area. The species involved apparently tolerate considerable temperature fluctuations.

3 .-Chlorinity seems to play an important part in determining the distribution of Streblus and Elphidium. Streblus appears to be mostly limited to brackish water whereas Elphidium thrives in waters of both low and normal chlorinity. One species of Elphidium was found only in waters of normal chlorinity, indicating that there are different chlorinity tolerances within the genus.

4.-There is no obvious consistent correlation be­tween median grain size and faunal trends.

5.-Many faunal trends could not be correlated with the physical conditions other than change in depth. Perhaps such trends will be found to correlate with turbidity conditions, light penetration, or character­istics of bottom plants.

6.-The weight percentages of Foraminifera and the number of species increase away from shore, because of more rapid sedimentation near shore and fairly stable normal chlorinity offshore.

7.-The prominences near shore have n1uch.the same fauna as the area slightly farther out, excepting for the appearance of Asterigina carinata d'Orbigny. The deeper water prominences are characterized by abun­dant A. carinata d'Orbigny, and the presence of Praesorites orbitolitoides (Hofker) and a few other species.

.ANNOTATED SYNONYMIES

This section is an alphabetized reference list of the species. Usually, the original and one subsequent reference are given for each species. All the species are figured, and arranged systematically on the plates to bring related forms together. The illustrations were made by Miss Mary Taylor and the author. The hypotypes are deposited in the U.S. National Museum, Washington, D. C.

Asterigerina carinata d 'Orbigny

Plate 31, figure 5

1839. Asterigerina carinata d'Orbigny, in Ramon de la Sagra, Histoire physique et naturelle de l'Ile de Cuba, A. Ber­trand, Paris, France, p. 118; plates published separately, v. 8, pl. 5, fig. 25; pl. 6, figs. 1-2. Recent, marine sand, Cuba and Jamaica.

1931. Asterigerina carinata d'Orbigny. Cushman, U. S. Natl. Mus. Bull. 104, pt. 8, p. 77, pl. 15, figs. 4, 5. Recent, West Indies.

Most specimens exhibit a small ventral umbo, a feature which is not found in the type, and this form may therefore represent a variety of d'Orbigny's species.

Bigenerina irregularis Phleger and Parker

Plate 29, figures 8, 9

1922. Bigenerina nodosaria d'Orbigny. Cushman, Carnegie Inst. Washington Pub. 311, p. 25, pl. 2, figs. 5, 6. Re­cent, Tortugas region. (Not B. nodosaria d'Orbigny, 1826.)

1951. Bigenerina irregularis Phleger and Parker, Geol. Soc. America, Mem. 46, pt. 2, p. 4, pl. 1, figs. 16-21. Recent, Gulf of Mexico.

This species ranges from 0 to 15 percent, and presents a fluctuating frequency distribution that is not corre .. lated with any of the environmental factors.

Bolivina striatula Cushman

Plate 31, figure 9

1922. Bolivina striatula Cushman, Carnegie Inst. Washington Pub. 311, p. 27, pl. 3, fig. 10. Recent, Tortugas region.

136 SHORTER CONTRIBUTIONS TO GENERAL GEOLOGY

1937. Bolivina striatula Cushman. Cushman, Cushman Lab. Foram. Research Special Pub. 9, p. 154, pl. 18, figs. 30, 31.

This species is very rare, and sporadic in occurrence.

Cancris sagra (d'Orbigny) Cushman

Plate 30, figure 9

1839. Rotalina sagra d'Orbigny, t'n Ramon de la Sagra, Histoire physique et naturelle de l'Ile de Cuba. A. Bertrand, Paris, France, p. 77, pl. 5, figs. 13-15. Recent, Cuba and Jamaica. ·

1931. Cancn·s sagm (d'Orbigny) Cushman, U. S. Natl. Mus. Bull. 104, pt. 8, p. 7 4, pl. 15, fig. 2.

1942. Cancris sagra (d'Orbigny) Cushman. Cush~an Lab. Foram. Research Contr., v. 18, pt. 4, p. 77, pl. 19, figs. 3-7.

This species is absent at shallow depths but fairly common at depths of 75 to 130 feet.

Discorbis floridanus Cushman

Plate 31, figure 1

1922. Discorbis jloridana Cushman, Carnegie Inst. Washington Pub. 311, p. 39, pl. 5, figs. 11, 12. Recent, Tortugas region.

This species is most abundant at depths of about 50 to 100 feet.

Elphidium discoidale (d'Orbigny) Cushman

Plate 30, figure 4

1839. Polystomella discoidalis d'Orbigny, in Ramon de la Sagra, Histoire physique et naturelle de l'Ile de Cuba. A. Bertrand, Paris, France, p. 76, pl. 6, figs. 23, 24 Recent, Cuba and Jamaica.

1930. Elphidi1.tm discoidale (d'Orbigny) Cushman, U. S. Natl. Mus. Bull. 104, pt. 7, p. 22, pl. 8, figs. 8, 9.

In the percentage-abundance counts, E. incertum (Williamson) var. mexicanttm Kornfeld (1931) was in­cluded with E. discoidale because the two forms seem to intergrade and the individual distributions were similar. Both forms are abundant throughout the area.

Elphidium fimbriatulum (Cushman)

Plate 29, figure 12

1918. Polystomellafimbriatulum Cushman, U.S. Geol. Survey Bull. 676, p. 20, pl. 8, figs. 5a, b. Miocene and Pliocene of

Florida.

This species is rare, and limited to the middle and offshore parts of the area.

Elphidium gunteri Cole var. galvestonense Kornfeld

Plate 30, figure 2

1925. Polystomella galvestonensis Applin (nomen nudum), Am. Assoc. Petroleum Geologists Bull., v. 9, no. 1, p. 84,

1931. Elphidiurn gunteri Cole var. galvestonensis Kornfeld, Stanford Univ. Dept. Geology, Contr., v. 1, no. 3, p. 87, pl. 15, figs. 1-3. Recent, littoral zone, Texas and Louisiana.

Generally, this species is most abundant in waters less than 40 feet deep; however, the general distribution was found to be about the same as that of E. discoidale (d'Orbigny) and E. poeyanum (d'Orbigny).

Elphidium poeyanum (d'Orbigny) Cushman

Plate 30, figure 6

1839. Polystomella poeyana d'Orbigny, in Ramon de la Sagra, Histoire physique et naturelle de l'Ile de Cuba. A. Bertrand, Paris, France, p. 55, pl. 6, figs. 25, 26. Recent, Cuba and Jamaica.

1930. Elphidium poeyanum (d'Orbigny) Cushman, U.S. Natl. Mus. Bull. 104, pt. 7, p. 25, pl. 10, figs. 4, 5.

1939. Elphidium poeyanum (d'Orbigny) Cushman, U.S. Geol. Survey Prof. Paper 191, p. 54, pl. 14, figs. 25, 26.

This cosmopolitan· species occurs in considerable abundance throughout the area investigated.

Eponides antillarum (d'Orbigny) Cushman

Plate 30, figure 8

1839. Rotalina (Rotalina) antillarurn d'Orbigny, in Ramon de la Sagra, Histoire physique et naturelle de l'Ile de Cuba. A. Bertrand, Paris, France, p. 75, pl. 5, figs. 4-6. Recent, Cuba. and Jamaica.

1922. Pulvinulina incerata Cushman, Carnegie Inst. Washing­ton Pub. 311, p. 51, pl. 9, figs. 1-3. Recent, Tortugas region.

1931. Eponides antillarum (d'Orbigny) Cushman, U. S. Natl. Mus. Bull. 104, pt. 8, p. 42, pl. 9, fig. 2. Recent, Florida.

Previous records of this species indicate a somewhat deeper water habitat than that studied in this work. As indicated by figures 11 to 13, it assumes some im­portance in the outer part of the area.

Globigerinoides rubra (d'Orbigny) Cushman

Plate 31, figure 6

1839. Glo~igerina rubra d'Orbigny, in Ramon de la Sagra, His­toire physique et naturelle de l'Ile de Cuba. A. Ber­trand, Paris, France, p. 82, pl. 4, figs. 12-14. Recent, Cuba and Jamaica.

1927. Globigerinoides rubra (d'Orbigny) Cushman, Cushman Lab. Foram. Research Contr., v. 3, p. 86.

This is the most abundant pelagic foraminifer in the material examined. A few other globigerinoids were noted but were not considered important enough to list.

This form appears at between 60 and 70 feet depth and is progressively more abundant away from shore.

Guttulina regina (Brady, Parker, and Jones) Cushman and Ozawa

Plate 29, figure 7

1870. Polymorphina regina Brady, Parker and Jones, Linnean Soc. Trans., v. 27, p. 241, pl. 41, fig. 32.

1930. Guttulina regina (Brady, Parker and Jones) Cushman and Ozawa, U.S. Natl. Mus. Proc., v. 77, art. 6, p. 34, pl. 6, figs. 1, 2. Recent, cosmopolitan.

This form has a sporadic occurrence, and rarely con­stitutes as much as 5 percent of the Foraminifera.

Hanzawaia strattoni (Applin)

Pia te 31, figure 4

1925. Truncatulina americana Cushman var. strattoni Applin, An. Assoc. Petroleum Geologists BtJl., v. 9, no. 1, p. 99, pl. 3, fig. 3. Miocene, Louisiana.

SHALLOW-WATER FORAMINIFERA IN THE GULF OF MEXICO

1931. Cibicides americana (Cushman) var. strattoni (Applin) Kornfeld, Stanford Univ., Dept. Geology, Contr., v. 1, no. 3, p. 82, check list. Recent, Texas coastal region.

This species is commonly placed in the genus Gibicides Montfort, 1808; however, it belongs in the genus Hanzawaia Asano (1944, p. 98), which differs from Oibicides in being mostly involute dorsally with the spire partly or entirely concealed by dorsal flaps, and in being generally not as coarsely perforate. Specimens referable to this species are sometimes identified with H. concentrica (Cushman) but they· are biconvex and have a rounded edge.

Haplaphragmoides canariensis (d'Orbigny) var. mexicana Kornfeld

Plate 29, figure 6

1931. Haplophragmoides canariensis (d'Orbigny) var. mexicana Kornfeld, Stanford Univ., Dept. Geology, Contr., v. 1, no. 3, p. 83, pl. 13, fig. 4. Recent, littoral zone of Texas and Louisiana.

Speciniens of this form are few and evidently fragile, as most of them are broken. The variety generally makes up less than 3 percent of the fauna.

Lagena tenuis (Bornemann)

Plate 29, figure 11

1855. Ovulina tenuis Bornemann, Deutsche geol. Gesell Zeitschr., Band 7, heft 2, p. 317, pl. 12, fig. 3. Oligocene, Germany.

1950. Lagena perlucida (Montagu) var. Cushman and McCulloch, Allan Hancock Pacific Expeditions, v. 6, no. 6, p. 343, pl. 46, figs. 3, 4.

This rare species is similar to many specimens that are identified as L. perlucida (Montagu). There is no similarity between Montagu's short, heavily costate species and this relatively smooth, elongate-ovate form that has ornamentation on the initial end only.

Massilina peruviana (d'Orbigny)

Plate 28, Figure 8

1839. Ouinqueloculina peruviana d'Orbigny, Voyage dans 1' Ameri­que Meridionale; Foraminiferes, v. 5, pt. 5, p. 73, pl. 4, figs. 1-3 (given on plate as 0. rneridionalis). Recent, coast of Chile.

1931. Massilina peruviana (d'Orbigny) Kornfeld, Stanford Univ., Dept. Geology, contr., v. 1, no. 3, p. 85, pl. 14, fig. 1. Recent, Texas and Louisiana.

This species rarely amounts to 2 percent of the foraminiferal fauna and it was lumped together with another miliolid, Quinqueloculina subquadra Hada, 1n the statistical data.

Nodobaculariella atlantica Cushman and Hanzawa

Plate 29, figure 4

1937. Nodobaculariella atlantica Cushman and Hanzawa, Cush­man Lab. Foram. Research Contr., v. 13, pt. 2, p. 42, pl. 5, figs. 7, 8. Recent, eastern coast of the U. S.

1948. !vodobaculariella atlantica Cushman and Hanzawa. Cush­man, Foraminifera, Harvard Univ. Press, key pl. 47, fig. 9.

The sjmilarity between this species and young speci­mens of Vertebralina cassis d'Orbigny is striking; how­ever, in the present form there are three chambers per whorl in the adult portion whereas in V. cassis there are only two in the early coiled portion.

N onionella atlantica Cushman

Plate 29, figure 10

1947. Nonionella atlantica Cushman, Cushman Lab. Foram. Re. search Contr., v. 23, pt. 4, p. 90, pl. 20, figs. 4, 5. Recent, Florida.

This species and Nonionella grateloupi (d'Orbigny} have the same distribution and were not differentiated in the present study.

P:anorbulina mediterranensis d'Orbigny

Plate 31, figure 3

1826. Planorbulina rnediterranensis d'Orbigny, Annales sci. nat., v. 7, p. 280, no. 2, pl. 14, figs. 4-6.

1931. Planorbulina rnediterranensis d'Orbigny. Cushman, U. S. N atl. Mus. Bull. 104, pt. 8, p. 129, pl. 24, figs. 5-8. 1 Recent, eastern and western Atlantic.

This form is rare, and seems to occur mostly in the area lying beneath at least 70 feet of water.

Planulina ornata (d'Orbigny) Cushman

Plate 31, figure 2

1839. Truncatu.lina ornata d'Orbigny, Voy. Am. Merid., v. 5, pt. 5, Foraminiferes, p. 40, pl. 6, figs. 7-9. Recent, off the coast of Chile.

1927. Planulina ornata (d'Orbigny) Cushman, Scripps Inst. Oceanography Bull., Tech. ser., v. 1, no. 10, p. 176, pl. 6, fig. 12. Recent, eastern Pacific.

This species is significant in the outer zone of the area studied, appearing at depths of 70 to 80 feet and increasing fairly rapidly in abundance seaward.

Poroeponides lateralis (Terquem) Cushman

Plate 30, figure 1

1878. Rosalina lateralis Terquem, Soc. geol. France, Mem., ser. 3, tome 1, no. 3, p. 25, pl. 2, fig. 11. Upper Pliocene, Isle of Rhodes.

1934. Rotalia repanda (Fichtel and Moll) Shupack, Am. Mus. Novitates, no. 737, p. 7, fig. 3. Pleistocene and Recent, western Long Island and New York harbor.

1944. Poroeponideslc:teralis (Terquem) Cushman, Cushman Lab. FQram. Research Special Pub. 12, p. 34.

1948. Poroeponides lateralis (Terquem) Cushman. Parker, Harvard Coli. Mus. Camp. Zoology Bull., v. 100, no. 2, p. 239 (list), pl. 1, fig. 17. Recent, Atlantic coastal waters.

A second species is included with this one in the frequency counts. It is figured on plate 30, figure 3.

Praesorites orbitolitoides Hofker

Plate 29, figure 5

1930. Praesorites orbitolitoides Hofker, Siboga-Exped., Mon. 4a, p. 149, pl. 55, figs. 8, 10, 11; pl. 57, figs. 4, 6; pl. 58; pl. 61, figs. 3, 14. Recent.

138 SHORTER CONTRIBUTIONS TO GENERAL GEOLOGY

This species was included with Peneroplis proteus d'Orbigny (1839, p. 60) in the frequency counts because the two occur together and the young stages of the two were sometimes difficult to distinguish.

Proteonina atlantica Cushman

Plate 28, figure 1

1944. Proteonina atlantica Cushman, Cushman Lab. Foram. Research Special Pub. 12, p. 5, pl. 1, fig. 4. Recent, off the New England coast.

1947. Proteonina difflugiformis (Brady) var. calcarea Cushman, Cushman Lab. Foram. Research Contr., v. 23, pt. 4, pl. 18, fig. 16. Recent off the Florida coast.

A series of specimens of this species shows that the type without the neck and that with a neck not only occur together but intergrade; the neckless form appears to have had the neck broken. Specimens of this form tend to be more abundant in the depressions.

Pyrgo clypeata (d'Orbigny)

Plate 28, figure 7

1846. Biloculina clypecda d'Orbigny, Foramimferes fossiles du basin tertiaire de Vienne (Autriche), Gide et Comp., Paris, p. 263, pl. 15, figs. 19--21. Tertiary (Miocene), Vienna basin.

This species is rare, and sporadic in occurrence.

Pyrgo comata (Brady) Cushman

Plate 28, figure 9

1881. Biloculina comata Brady, Quart. Jour. Micro. Soc., v. 21, p. 45.

1884. Bilocidina comata Brady. Brady, Challenger Rept., Zo­ology, v. 9, p. 144, pl. 3, fig. 9. Recent, cosmopolitan.

1929. Pyrgo comata (Brady) Cushman, U. S .. Natl. Mus. Bull. 104, pt. 6, p. 73, pl. 19, fig. 8. Recent, mostly deep water of the Atlantic.

This species is rare, and sporadic in the sediments studied. It ra.rely makes up more than 2 percent of the foraminiferal fauna.

Quinqueloculina compta Cushman

Plate 28, figure 2

1947. Quinqueloculina compta Cushman, Contr. Cushman Lab. Foram. Res., v. 23, pt. 4, p. 87, pl. 19, fig. 2.

The range and percentage distribution of this species was mostly non-significant within the area of this study.

Quinqueloculina lamarckiana d'Orbigny

Plate 28, figure 3

1839. Qidnqueloculina lamarckiana d'Orbigny, in Ramon de la Sagra, Histoire physique et naturelle de l'lle de Cuba. A. Bertrand, Paris, France, p. 189, pl. 11, figs. 14, 15. Recent, Cuba and Jamaica.

1930. Quinqueloculina lamarckiana d'Orbigny. Cushman, Stan­ford Univ., Dept. Geology, Contr., v. 1, no. 1, p. 10, pl. 1, figs. 9, 10. Recent, near the Channel Islands off southern Calif.

This species exhibits a remarkably uniform percent­age distribution nearly throughout the three traverses. The only major exceptions are the small percentage increases on the prominences in shallow water.

Quinqueloculina subquadra Hada

Plate 28, figure 4

1931. Quinqueloculina subquadra Hada, Tohoku Imp. Univ. Sci. Repts., 4th ser., v. 6, p. 78, pl. 31. Recent, near Japan

This species is Fare and unimportant in the area.

Rectobolivina advena (Cushman)

Plate 31, figure 8

1922. Siphogenerina advena Cushman, Carnegie Inst. Washing­ton Pub. 311, p. 35, pl. 5, fig. 2. Recent, Tortugas region.

It is rare, and occurs mostly in the outer zone.

Reussella atlantica Cushman

Plate 31, figure 7

1947. Reussella spinulosa (Reuss) var. atlantica Cushman, Cush­man Lab. Foram. Research Contr., v. 23, pt. 4, p. 91, pl. 20, figs. 6, 7. Recent, off the southeastern coast of the United States.

There is a gradual increase in the frequency of this species seaward from its first appearance at depths of about 40 or 50 feet.

Sigmoilina antillarum (d'Orbigny)

Plate 29, figure 1

1839. Spt'rdoculina anWlarum d'Orbigny, in Ramon de La Sagra, Histoire physique et naturelle de l'Ile de Cuba. A. Bertrand, Paris, France, p. 166, pl. 9, figs. 3; 4. Recent, Cuba and Jamaica. ·

1944. Spiroloculina anttllarum d'Orbigny. Cushman and Todd, Cushman Lab. Foram. Research Special Pub. 11, p. 44, pl. 6, figs. 28-32. Recent, West Indies.

This species is rare, and rather sporadic in occur­rence, but was found most consistently in the outer zone. It is probably (Cushman, 1922, p. 66) conspecif­ic with S. subpoeyana (Cushman).

Streblus beccarii (Linne) var. sobrinus (Shupack)

Plate 30, figure 7

1931. Rotalia beccarii (Linne) var. parkinsoniana (d'Orbigny). Kornfeld, Stanford Univ., Dept. Geology, Contr., v. 1, no. 3, p. 90, pl. 13, fig. 1. Recent, Texas and Louisiana.

1934. Rotalia beccarii (Linne) var. sobrina Shupack, Am. Mus. Novitates, no. 737, p. 6, fig. 4. Recent, Pleistocene, New York harbor.

This variety is characteristic of the nearshore area, making up more than 20 percent of the foraminiferal constituents out to a depth of about 55 feet Streblus beccarii (Linne) var. tepidus (Cushman) was included with this variety in the statistical study because the two varieties have the same distribution.

SHALLOW-WATER FORAMINIFERA IN THE GULF OF MEXICO 139

Streblus rolshauseni (Cushman and Bermudez)

Plate 30, figure 5

1946. Rotalia rolshauseni Cushman and Bermudez, Cushman Lab. Foram. Research Contr., v. 22, p. 119, pl. 19, figs. 11-13. Recent, Gulf of Mexico.

The holotype of this species was reported from a depth of 83 feet off the Rio Grande. In the present study it was found to be common in shallow water, more rare offshore, and to disappear at a depth of about 80 feet.

Textularia candeiana d'Orbigny

Plate 29, figure 2

1839. Textularia candeiana d'Orbigny, in Ramon de la Sagra, Histoire physique et naturelle de l'Ile de Cuba. A. Bertrand, Paris, France, p. 143, pl. 1, figs. 25-27. Recent, Cuba and Jamaica.

1948. Textularia candeiana d'Orbigny. Parker, Harvard Coil. Mus. Comp. Zoology Bull., v. 100, no. 2, 240, pl. 2, fig. 5. Recent, continental shelf between Maine and Maryland.

This species is sporadic in occurrence but seems to be most abundant on the prominences. Its greatest abundance is on prominence 4 (fig. 7). Parker (in the reference above) indicates that this species occurs in his zone 3 (90-300 .meters) along the Atlantic coast, but is very rare.

Textularia mayori Cushman

Plate 29, figure 3

1922. Textularia mayori Cushman, Carnegie Inst. Washington Pub. 311, p. 23, pl. 2, fig. 3. Recent, Tortugas region.

It was noted that this species exhibits considerable variation in the length of the spinose projections of the chambers.

Triloculina squamosa Terquem

Plate 28, figure 6

1878. Triloculina squamosa Terquem, Soc. geoL France, Mem., ser. 3, tome 1, no. 3, p. 59, pl. 5, fig. 26. Upper Plio­cene, Isle of Rhodes.

Several specimens were found which belong in this species; however, because of the rarity of this form and allied arenaceous miliolids, this is the only form figured. In the percentage counts, the arenaceous miliolids were lumped together when it was ascertained that none of them amounted to a significant percentage alone.

Triloculina trigonula (Lamarck) d'Orbigny

Plate 28, figure 5

1804. Miliolites trigonula Lamarck, Ann. Nat. Hist. Paris Mus., v. 5, p. 351, no. 3.

1807. Miliolites trigonula Lamarck. Lamarck, Ann. Nat. Hist. Paris Mus., v. 9, pl. 17, fig. 4.

1858. Triloculina trigonula (Lamarck) d'Orbigny, Ann. Sci. Nat., v. 7, p. 299, no. 1, pl. 16, figs. 5-9.

1929. Triloculina trigonula (Lamarck) d'Orbigny. Cushman, U. S. Natl. Mus. Bull. 104, pt. 6, p. 56, pl. 12, figs. 10, 11; pl. 13, figs. 1, 2. , i. ., '· ~ ~~ t4 1~

' ... -·-;;w:;;;r

This is a rare sporadic species in the samples studied. There is considerable variation in the angularity of the test; it is quite angular in some specimens and rounded in others.

Virgulina schreibersiana Czjzek

Plate 31, figure 10

1848. Virgulina schreibersiana Czjzek, Haidinger's Naturwiss. Abb., Band 2, p. 11, pl. 13, figs. 18-21. Miocene, Vienna Basin.

1937. Virgulina schreibersiana Czjzek. Cushman, Cushman Lab. Foram. Research Special Pub. 9, p. 13, pl. 2, fig~ 11-20. .• ~

This species was rather common at some of the stations, particularly in the outer zone.

BIBLIOGRAPHY

Acosta, J. T., 1940, Algunos Foraminiferos nuevas de las costas Cubanas: Torreia, Museo Poey, Universidad de la Habana, Cuba, no. 5, p. 3-6.

Asano, K., 1944, Hanzawaia, a new genus of Foraminifera from the Pliocene of Japan: Geol. Soc. Japan Jour. Tokyo, v. 51, no. 606, pp. 97, 98.

Brady, H. B., 1884, Challenger Rept., Zoology, v. 9. Cushman, J. A., 1918, Some Miocene Foraminifera of the coastal

plain of the United States: U. S. Geol. Survey Bull. 676. --- 1921, Foraminifera from the north coast of Jamaica:

U. S. Natl. Museum Proc., v. 59. --- 1922, Shallow-water Foraminifera of the Tortugas region:

Carnegie Inst. Washington Pub. 311. --- 1926, Recent Foraminifera from Puerto Rico: Carnegie

Inst. Washington Pub. 344. d'Orbigny, A. D., 1826, Annales sci. nat., v. 7, no. 19, p. 294. --- 1839, in Ramon de la Sagra, Histoire physique et natu­. relle de l'Ile de Cuba. A. Bertrand, Paris. Geyer, R. A., 1950, A bibliography of the Gulf of Mexico: Texas

Jour. Science, v. 2, no. 1.

Hedberg, H. D., 1934, 1934, Some Recent and fossil brackish to freshwater Foraminifera: Jour. Paleontology, v. 8, p. 469-476.

Joesting, H. R., and Frautschy, J. D., 1947, Reconnaissance gravity map of part of the Gulf of Mexico: U. S. Geol. Survey Geophys. Inv., prelim. map.

Kornfeld, M. M., 1931, Recent littoral Foraminifera from Texas and Louisiana: Stanford Univ., Dept. Geology, Contr., v. 1, no. 3.

Lalicker, C. G., and Bermudez, P. J., 1941, Some Foraminifera of the family Textulariidae collected by the first Atlantis ex­pedition: Torreia, Museo Poey, Universidad de la Habana, Cuba, No.8, September 27.

Lowman, S. W., 1949, Sedimentary facies in Gulf Coast: Am. Assoc. Petroleum Geologists Bull., v. 33, no. 12, p. 1939-1997.

Myers, E. H., 1943, Life activities of Foraminifera in relation to marine ecology: Am. Philos. Soc. Proc., v. 86, no. 3, p. 439-458.

Natland, M. L., 1933, The temperature and depth distribution of some recent and fossil Foraminifera in the southern Cali­fornia region: Scripps Inst. Oceanography Bull., Tech. ser., v. 3, no. 10, p. 225-230.

140 SHORTER CONTRIBUTIONS TO GENERAL GEOLOGY

Parker, F. L., 1948, Foraminifera of the continental shelf from the Gulf of Maine to Marylanq: Harvard Coll. Mus. Comp. Zoology ~ull., v. 100, no. 2, p. 214-241.

Phleger, F. B., 1942, Foraminifera of submarine cores from the continental slope, pt. 2: Geol. Soc. America Bull., v. 53, p. 1073-1098.

Phleger, F. B., and Parker, F. L., 1951, Gulf of Mexico Forami­nifera: Geol. Soc. America Mem. 46.

Said, Rushdi, 1950, The distribution of Foraminifera in the northern Red Sea: Cushman Foundation Foram. Research Contr., v. 1, p. 13.

Vaughan, T. W., 1918, Some shoal-water bottom samples from Murray Island, Australia, and comparisons of them with samples from Florida and the Bahamas: Carnegie lnst. Wash­ington Pub. 213.

Page advena, Rectobolivina ___ --------· -------------- 198, pl. 31

Siphogenerina _______ ------------- c------------ 138 americana strattoni, Oibicides______________________ 137

Truncatulina. ---------------------------- 136 Annotated synonymies ________________ .. -------- 135-,139 antillarum, Eponides_________________ 132,135,196, pl. 30

Rotalina (Rotalina) __ ------------------------ 136 Sigmoilina. ------------------------------ 198, pl. 29 Spiro toculina •. --------------------------- ____ 138

Asterigerina carinata __________________ 132,134, 196, pl. 31 atlantica, Nodobaculariella ____________________ 197, pl. 29

Nonionella _______________________________ 197, pl. 29 Proteonina _______________________________ 198, pl. 28 Reussella _________________________________ 1:!18, pl. 31

spinulosa ___________________ --------- _____ 138

beccarii parkinsonia, Rotalia_______________________ 138 sobrina, Rotalia_______________________________ 138 sobrinus, Streblus _____________________ 132,138, pl. 30 Streblus ______ _____ ------ ____________________ 132, 134 tepidus, Streblus ____________________________ 132,134

Bigenerina_ irregularis _________________________ 196, pl. 29

nodosaria.------------------------------------ 135 Biloculfna clypeata __ ___ --- _ ----- ____ ------ _ ___ ___ _ 138

comata ___ __________ -- __________ ----------- ___ _ 138 Bolivina striatula _________________________ 135,136, pl. 31

canariensis mexicana, Haplaphragmoides ______ 197, pl. 29 Cancris sagra _________________________ 132,135,196, pl. 30 candeiana, Textularia _____________________ 135,199, pl. 29 carinata, Asterigerina _________________ 132,134,136, pl. 31 cassia, Vertebralina ____ ---- ____ ------------ ___ __ _ _ _ 137 Chlorinity, summary of importance______________ 135 Oibicides americana strattonL--------------------- 137 clypeata, Biloculina. ------------------------------ 138 Pyrgo ____________________________________ 198, pl. 28

comata, Biloculina. _ ------------------------------ 138 Pyrgo ____________________________________ 198, pl. 28 compta, Quinqueloculina ______________________ 198, pl. 28

concentrica, Hanzawaia. _ ----------------------- 134,137 crispum, Elphidium_______________________________ 134

Depth, summary of importance._---------------- 135 diffiugiformis calcarea, Proteonina. __ -------------- 138 discoidale, Elphidium _____________________ 132,196, pl. 30 discoidalis, Polystomella __ ------------ ___ _ ___ __ _ __ _ 136

Discorbis ftoridana. _ ------------------------------ 136 ftoridanus ________________________ 132,134,196, pl. 31

Elphidium __________________________ ------------ 134,135

crispum ___ ----------------------------------- 134 discoidale _____________________________ 132,196, pl. 30

fimbriatulum. ------------------------ 134,196, pl. 29 gunteri galvestonense __________________ 132,196, pl. 30 incertum mexicanum__________________________ 136 paeyanum ____________________________ 132, 136, pl. 30

Eponides antillarum __________________ 132,135,196, pl. 30

Faunal analysis, general features __________________ ur126

fimbriatulum, Elphidium. ------------'~---- 134,196, pl. 29 Polystomella. _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 136

fisridana, Discorbis __________________ -------------- 136 ftoridanus, Discorbis. ----------------- 132,134,156, pl. 31

galvestonense, Elphidium gunteri. _ _ _ _ _ _ _ _ _ 132, 196, pl. 30 galvestonensis, Polystomella_______ ___ _ ___ ___ __ __ __ _ 136

INDEX

[Italic numbers indicate descriptions]

Pap Globigerina rubra________________________________ __ 136 Quinqueloculina compta_ --------------------- 138, pl. 28 Globigerinoides rubra __________________ 132,134,136, pl. 31 lamarckiana __________________________ 134,198, pl. 28 Grain size, summary of significance_______________ 135 meridionalis___________________________________ 137 grateloupi, Nonionella____ _ __ ___ ___ _ __ _ __ _ __ _ __ _ _ _ _ 137 peruviana ___ ___________ --------------------- __ 137

gunteri galvestonense, Elphidium. --------- 132,136, pl. 30 subquadra __ -------------------------- 137,198, pl. 28 Guttulina regina------------------------------ 136, pl. 29

Haplaphragmoides canariensis mexicana. ______ 197, pl. 29 Hanzawaia concentrica __________________________ 134,137

strattoni. _____________________ 132,134,135,196, pl. 31

incerata, Pulvinulina____ __ _ _ _ _ _ _ _ _ _ _ _ _ _ __ __ _ __ __ _ _ 136 incertum mexicanum, Elphidium__________________ 136 Introduction ___________ -------------------------- 125 irregularis, Bigenerina.----------------------- 196, pl. 29

Lagena perlucida var ------------------------------ 137 tenuis. _ ---------------------------------- 197, pl. 29

lamarckiana, Quinqueloculina _____________ 134,198, pl. 28

lateralis, Poroeponides. _ ---------------------- 197, pl. 30 Rosalina ____ _ ----------------- _ -------- __ --- __ 137

Massilina peruviana _____________________ ~---- 197, pl. 28

mayori, Textularia---------------------------- 199, pl. 29 mediterranensis, Planorbulina _________________ 157, pl. 31

meridionalis,. Quinqueloculina. _ ------------------- 137 Method of study ____ ---------------------------- 126 11UIXicana, Haplaphragmoides canariensis _______ 197, pl. 29 mexicanum, Elphidium incertum. ----------------- 136 Miliolites trigonula ______________ _ ----- ____ ---- _ __ _ 139

Nodobaculariella atlantica _____________________ 197,pl. 29

nodosaria, Bigenerina. __ -------------------------- 135 Nonionella atlantica.------------------------- 137, pl. 29

grateloupL ___ ------ _________________ -- _ _ _ _ _ __ 137

orbitolitoides, Praesorites. _ ------------ 132,135,197, pl. 29 ornata, Truncatulina______________________________ 137

Planulina. ----------------------------------- 137 Ovulina tenuis. _____ ---------------------------- __ 137

parkinsonia, Rotalia beccariL_____________________ 138

Peneroplis proteus ______ -------------------------- 138 perlucida var., Lagena_____________________________ 137

peruviana,·Massilina .. ------------------------ 137, pl. 28 Quinqueloculina. _. ------------------------- __ 137

Planorbulina mediterranensis. ---------------- 197, pl. 31 Planulina ornata ____________________ ~---- 132, 137,pl. 31 poeyana, Polyrstomella___ ___ _ _ __ _ __ _ _ _ _ ___ _ __ ___ __ _ 136 poeyanum, Elphidium ____________________ 132,196, pl. 30 Polymorphina regina______________________________ 136 Polystomella discoidalis _________________ ----------- 136

jimbriatulum __________ ------------------------ 136 galvestonensis _ ~- _________________ ------ __ _ ___ _ 136

poeyana .. __ ----------------------------------- 136 Poroeponidesluteralis ________________________ 197, pl. 30

sp ____ ---------------------------------------- pl. 30 Praesorites orbitolitoides .. ------------- 132,135,197, pl. 29 Previous work ___________ ------_________________ 125-126 Prominences, summary of significance____________ 135 Proteonina atlantica __________________________ 198, pl. 28

difflugiformis calcarea_------------------------ 138 proteus, Peneroplis ____ _____ --- ______________ --- _ __ 138

Pulvinulina incerata .. _ ---~-------------- ---------- 136 Pyrgo clypeata .. _____ ---------------------- ___ 138, pl. 28

comata ___________________________________ 138, pl. 28

RectoboUvina advena __________________________ 138, pl. 31 regina, Guttulina _____________________________ 136, pl. 29

Polymorphina. __ ----------------------------- 136 repanda, Rotalia. ----------------------------- 137

Reussella atlantica ____________________________ 138, pl. 31

spinulosa atlantica_--------------------------- 138 rolshauseni, Rotalia .. ------------------------------ 139

Streblus __________________________ 132,134,199, pl. 30 Rosalina lateralis_____ ___ _ ___ __ _ ___ _ _ __ __ _ ___ ___ _ _ _ 137 Rotalia beccarii parkinsoniana_____________________ 138

sobrina. __ -------------------------------- 138 Rotalia repanda ___ -------------------------------- 137

rolshauseni _____ _______ ----- _ --- ______ ------ _ __ 139 (Rotalina) antillarum, Rotalina____________________ 136 Rott.Zlina (Rotalina) antillarum____________________ 136

sagra __ --------------------------------------- 136

rubra, Globigerina _______ _____ ----·---------------- 136 Globigerinoides ___________________ 132, 134, 196, pl. 31

sagra, Cancris. ---------------------- 132, 135, 196, pl. 30 Rotalina ___________________________ --------- _ _ 136

Samples, location and preparation ___________ 126, pl. 27 schreibersiana, Virgulina ______________________ 139, pl. 31

Sigmoilina antillarum. ----------------------- 138, pl. 29 Siphogenerina advena _____ ___ ------- _ --- ________ --- 138

sobrina, Rotalia beccarii. __ ------------------------ 138 sobrinus, Streblus beccariL--------------- 132, 198, pl. 30 spinulosa atlantica, Reussella---------------------- 138 Spiroloculina antillarum .. _ ------------------------ 138 squamosa, Triloculina.----------------------- 199, pl. 28 stratton£, Cibicides americana---------------------- 137

Hanzawaia __________________ 132, 134, 135, 196, pl. 31 Streblus ________________________________ 126, 132, 134, 135

beccarii.. ____________________________________ 132, 134 beccarii sobrinus ______________________ 132, 138, pl. 30

tepidUS--------------------------------- 132, 138 rolshausenL-------------------- 132, 134, 139, pl. 30

striatula, Bolivina------------------------ 196, 136, pl. 31 subquadra, Quinqueloculina. _ ------------ 137, 138, pl. 28'

Temperature, summary of importance____________ 135

tenuis, Lagena. __ ---------------------------- 137, pl.. 29 OtJulina _____ ________ ------- ____ --------------- 137

tepidus, Streblus beccariL----------------------- 132, 134 Textularia candeiana _____________________ 135, 1~9, pl. 29

mayori_ __________________________________ 199, pl. 29

trigonula, .Miliolites. ________________ -------------- 139 Triloculina _______________________________ 199, pl. 28

Triloculina squamosa------------------------- 199, pl. 28 trigonula .. -------------------------------- 199, pl. 28

Truncatulina americana strattonL----------------- 136 or~a- _ -------------------------------------- 137

Vertebralina cassia._------------------------------ 137 Virgulina schreibersiana. --------------------- 199, pl. 31

Zonation, zone 1.------------------------------- 132, 134 zone 2 .. _ -------------- __ ---------------------- 134 zone 3-------------------------------------- 134, 135

141

PLATES 28-31

'

PLATE 28

FIGURE 1. Proteonina atlantica Cushman (p. 138). Hypotype, USNM 547603, station 81. a, side view; h, apertural view, X 104.

2. Ouinqueloculina com pta Cushman (p. 138). Hypotype, USNM 547606, station 46. a, c, opposite sides; b, apertural view, X 94.

3. Ouinqueloculina lamarckiana d'Orbigny (p. 138). Hypotype, USNM 547607, station 83. a, c, opposite sides; b, apertural view, X 68.

4. Quinqueloculina subquadra Hada (p. 138). Hypotype, USNM 547607, station 83. a. c, opposite sides; b, apertural view, X 68.

5. Triloculina trigonula (Lamarck) d'Orbigny (p. 139). Hypotype, USNM 547618, station 83. a, c, opposite sides; b, apertural view, X 60.

6. Triloculina squamosa Terquem (p. 139). Hypotype, USNM 547617, station 46, a. c, opposite sides; b, apertural view, X 94.

7. Py1go clypeata (d'Orbiguy) (p. 138). Hypotype, USNM 547604, station 46. a, apertural view; b, side view, X 60.

8. Massilina pe1uviana (d'Orbigny) Kornfeld (p. 137). Hypotype, USNM 547597, station 83. a, c, side views; b, apertural view, X 60.

9. Pyrgo comata (Brady) Cushman (p. 138). Hypotype, USNM 547605, station 90. a, side view; b, apertural view, X 112.

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PLATE 29

FmuRE 1. Sigmoilina antillmum (d'Orbiguy) (p. 138). Hypotype, USN M 547614, station 183. a, c, side views ; b, apertural view, X 99.

2. Textularia candeiana (d'Orbiguy) (p. 139). Hypotype, USNM 547615, station 86. a, side view; b, apertural view, X 60.

3. Textularia mayO',i (Cushman (p. 139). Hypotype, USNM 547616, station 104. a, side view; b, apertural view, X 60.

4. Nodobaculmiella atlantica Cushman and Bermudez (p. 137). Hypotype, USNM 547598, station 183. a. side view; b, apertural view, X 60.

5. Praesorites orbitolitoides Hofker (p. 137). Hypotype, USNM 547613, station 192. Side view, X 38.

6. Haplaphragmoides canariensis (d'Orbiguy) var. mexicana Kornfield (p. 137). Hypotype, USNM 547595, station 81. a, side view; b, edge view, X 100.

7. Guttulina regina (Brady, Parker and Jones) Cushman and Ozawa (p. 136). Hypotype, USNM 547695, station 68. a, side view; b, apertural view, X 94.

8. Bigenerina inegulan·s Phleger and Parker (p. 135). Hypotype, USNM 547582, station 81. a, side view; b, apertural view, X i5.

9. Bigenerina irregularis Phleger and Parker (p. 135). Hypotype, USNM 547583, station 86. a, c, side views; b, apertsral view, X 60.

10. Nonionella atlantica Cushman (p. 137). Hypotype, USNM 547599, station 87. a, c, opposite sides; b, edge view, X 106.

11. Lagena tenuis (Bornemann) (p. 137). Hypotype, USNM 547596, station 68. Side view, X 100.

12. Elphidium fimbriatulum (Cushman) (p. 136). Hypotype, USNM 547590, station 81. a, side view; b, apertural view, X 68.

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9a

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PLATE 30

FIGURE 1. Poroeponides lateralis (Terquem) Cushman. (p. 137) Hypotype, USNM 547602, station 187. a, ventral view; b, edge view; c, dorsal view. X 63.

2. Elphidium gunteri Cole var. galvestonense Kornfeld. (p. 136) Hypotype, USNM 547589, station 12. a, side view; b, edge view. X 94.

3. Poroeponides sp. (p. 137) Hypotype, USNM 547602b, station 187. a, ventral view; b, edge view; c, dorsal view. X 63.

4. Elphidium discoidale (d'Orbigny) Cushman. (p. 136) Hypotype, USNM 547588, station 60. a, side view; b, edge view. X 68.

5. Streblus rolshauseni (Cushman and Bermudez). (p. 139) Hypotype, USNM 547612, station 57. a, ventral view; b, apertural view; c, dorsal view. X 100.

6. Elphidium poeyanum (d'Orbigny) Cushman. (p. 136) Hypotype, USNM 547591, station 58. a, side view; b, edge view. X 94.

7. Streblus beccarii (Linne) var. sobrinus (Shu pack). (p. 138) Hypotype, USNM 547611, station 21. a, dorsal view; b, edge view; c, ventral view. X 100.

8. Eponides antillarum (d'Orbigny) Cushman. (p. 136) Hypotype, USNM 547592, station 97. a, dorsal view; b, apertural view; c, ventral view. X 87.

9. Cancris sagra (d'Orbigny) Cushman. (p. 136) Hypotype, USNM 547585, station 182. a, edge view, b, ventral view; c, dorsal view. X 100.

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PLATE 31

FIGURE 1. Discorbis jloridanus Cushman. (p. 136) Hypotype, USNM 547587, station 15. a, ventral view; b, edge view; c, dorsal view. X 137.

2. Planulina ornata (d'Orbigny) Cushman. (p. 137) Hypotype, USNM 547601, station 187. a, vental view; b, edge view; c, dorsal view. X 63.

3. Planorbulina mediterranensis d'Orbigny. (p. 137) Hypotype, USNM 547600, station 183. a, ventral view; b, edge view; c, dorsal view. X 63.

4. Hanzawaia strattoni (Applin). (p. 136) Hypotype, USNM 547586, station 83. a, ventral view; b, apertural view; c, dorsal view. X 87.

5. Asterigerina carinata d'Orbigny. (p. 135) Hypotype, USNM 547581, station 192. a, dorsal view; b, apertural view; c, ventral view. X 63.

6. Globigerinoides rubra (d'Orbigny) Cushman. (p. 136) Hypotype, USNM 547593, station 179. a, ventral view; b, edge view; c, dorsal view. X 87.

7. Reussella atlantica Cushman. (p. 138) Hypotype, USNM 547610, station 81. a, side view; b, apertural view. X 100.

8. Rectobolivina advena (Cushman). (p. 138) Hypotype, USNM 547609, station 81. a, side view; b, apertural view. X 100.

9. Bolivina striatula Cushman. (p. 135) Hypotype, USNM 547584, station 94. a, side view; b, apertural view. X 210.

10. Virgulina schreibersiana Czjzek. (p. 139) Hypotype, USNM 547619, station 81. a, side view; b, apertural view. X 100.

U. S. GOVERNMENT PRINTING OFFICE i lts4

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