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Property of Mote Marine Laboratory, Sarasota, Florida.MULLET
( On Oct . 18th, 1934, the small l abor a tory pool was s eined with a minnow se ine in order to s ecure specimens of the Thornton Isl and mullet . One spe ci~men was obtai ned having a standard lengt h of 34 units on the Bureau of Fisheries t cm. s cale , i . e . 17 cm. It was in good condition.
On Oct . 22nd the Thornton Is . pool was netted for the first time this year and two spe cimens were removed and brought to the l aboratory . The following notes were taken:
Fish No . 1 - Length l ast s cale (center of caudal fin) - 43 . 75 Standar d measurement - 46.5 Injected on lef8 side directly back of pectoral fin with India ink . First dorsa 1 spi ne broken.
Fish No . 2 - Length l as t s cale (center of caudal fin) - 44 Standard length - 48 I nje cted same way as No . 1 fi sh .
During the pro cess of t aking the measurements both fish los t scales. Bot h these mullet were pl aced i n the l abor atory pool .
On Oct . 26th one of these fish was noted in shallow water, evidently Si ck, and was reported spotted with sores . The fish was never recovered as dead and has not been seen since .
On Nov . 17th Thornton Is . pool was again netted and two mullet procured . 12 mullet were seen to jump over the net . The pool was cons i derably smaller , the deepest part being only knee dee as agains t hi p depth on the previous seining .
Dr . Nol and , protozoologi st of the University of Wisconsin, took sampl es of the pool and has supplied the fol lowing notes :
Character i st ic al ga abundant .
Fine slender diatoms f a irly common; wide diatoms not as abundant as in bay.
Cryptomonad fl agella tes quite abundant .
Dinoflagellates f a irly common .
Wr act ically no copepods; a few rotifers present; nematodes fairly common.
Ciliates fairly common and the f ollowing observwed:
Loxophyllum set i gerum Lacrymaria corona ta Eupl otes al a tus Pleuronema coronata
Property of Mote Marine Laboratory, Sarasota, Florida.(Mullet continued)
A sample of water from Thorntcn Is . pool was prought to the l aboratory and the specific gr avity determi ned , viz . 1005 . 5.
Both fish were rbrought to the l aboratory for di sse cting pur poses and the following measurements were made:
Standard length - 42 . 5 cm. ! otal length - 50 . cm. Length of center
of caudal fin - 47. am.
D. IV - I, 8 A. III, 8
,No . of scales - 41
Snout - 1 cm. Head - 4 . 8 cm.
No scales noted on second dorsal fin ; a few were present ar ound the sp i nes of the anal fin and many around the dorsal and ventral edges of the caudal fin .
Dark longitudinal stripes we re very defi nite.
No par~sitic copepods noted on the gills .
The fish was ident ified as MugU cephalus.
The lining of the body cavity was bl ack, the pi gment coming off on to the hands . There was consi derable fat ar ound the i ntes tine which measured 88 cm. l ong . The oesophagus and stomach were empty; the intestine contained a brownish fluid .
On Nov . 19th two mullet s were secured fr om the fish market and di ssected and f ound to contain red and whi te roe respe ctively.
red roe - 78 . 5 cm. ; ovary - 16 cm. , soft . white roe - 68 cm. ; test i s - 13 cm. , hard.
A par as itic copepod (an Ergas ilid) was quite abundant on the gills of one of the above fish.
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