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FISHERY BULLETIN OF THE FISH AND WILDLIFE SERVICE 



including 28 not found elsewhere. Both floras 

 are characterized also by a number of remarkable 

 species of Campy Iodise xis. As an explanation, 

 Mann implies the possibility of parallel develop- 

 ment and discoimts the idea of transfer or dispersal 

 between the two localities. Other workers take 

 exceptions to the whole idea of attaching any 

 significance to the common appearance of diatom 

 species in the two widely separated areas. At 

 least, it is an interesting observation and one not 

 to be neglected. 



Among the Campeche Bay diatoms, mostly 

 registered in Schmidt's Atlas (1876-) are many 

 species and varieties bearing the name campe- 

 chiana, such as Amphora crassa Greg. var. campe- 

 chiana Grun., A. grevilleana Greg. var. campechiana 

 Grun., Campylodiscus campechianus Deby, Coc- 

 coneis campechiana Cleve, Cosinodiscus gemifer 

 Ehr. var. campechianus Ratt., C. marginulatus 

 Ratt. var. campechiana Grun., Endictya campe- 

 chiana Grun., Glyphodesmis campechiana Boyer, 

 Navicula campechiana Grun., Nitzchia campechiana 

 Grun., Stephanopyxis campechiana Grun., Surirella 

 campechiana Hust., Triceratium campechianum 

 (Grun.?), and others, indicating a very diverse 

 and novel flora. Yet we have little information 

 as to the exact source and extent of the material 

 from this sizeable area, and it is likely that more 

 thorough and careful survey may add new findings 

 to this apparently most interesting locality. 



If the great diversity of the Campeche Bay 

 diatom flora and the yield of new forms is any 

 indication of what might be expected from ex- 

 amination of other places in the long stretches of 

 unexplored shore line of the Gulf, interesting pros- 

 pects are in order. It must be remembered, 

 however, that the yield of new forms from Cam- 

 peche Bay came mostly many years ago when 

 fewer species were known from other places. 



MOBILE BAY 



Probably one of the more intensivel}' studied 

 areas of the Gulf coast thus far is Mobile Bay. 

 A list of diatoms from this area published by 

 Cunningham (1889), one of the few diatom stu- 

 dents local to the Gulf area, includes 37 genera and 

 137 species, but is probably far from complete. 

 Cox (1901) who identified the diatoms in Cunning- 

 ham's collection, furnished a useful but clearly 

 incomplete list of 29 genera and 62 species. This 

 material obtained from George H. Taylor, Wm. 



McNeil, and his own collecting, includes typically 

 fresh water, brackish, and marine forms. Since 

 Cox specifically says that all the specimens are 

 from Mobile Bay it is obvious that fresh water 

 species in this collection were brought in by 

 streams. This list is also correlated with records 

 of George H. Taylor from Tampa Bay. 



One form from salt marshes at Mobile found 

 in Cunningham's material and named by Grunow 

 is sufficiently remarkable and well known to 

 deserve particular mention. It is Terpsinoe 

 intermedia Grun., a diatom of abnormal structure 

 with quite symmetrical adjutment on the central, 

 valve face (see Schmidt's Atlas, 1876, plates 198- 

 200). The species is closely related to T. musica 

 Ehr., typical of the Gulf coast. It is evidently 

 plentiful in its original locality near Mobile. 



TORTUGAS AND WEST COAST OF 

 FLORIDA 



Extensive collections made by the writer at 

 Tortugas and around Tampa Bay are in process 

 of study, and some observations based on them 

 are included in this summary. George H. Taylor 

 made records from Tampa Bay as above cited. 

 Mann prepared a list of diatoms of Pensacola Bay. 

 The writer's report (unpublished) on plankton 

 diatoms of the west Florida coast, off Tampa 

 and Fort Myers, to E. Lowe Pierce of the Univer- 

 sity of Florida, includes 35 genera and 82 species 

 and varieties. Some species of Chaetoceros and 

 Hemidiscus included in this list were found in 

 heavy concentrations, a fact which indicates that 

 Gulf coastal waters are, at times, very productive. 



From the studies mentioned above an inference 

 may be drawn that mixed calcareous and organic 

 muds of the west coast of Florida provide favorable 

 environment and adequate supply of nutrients to 

 support a generally rich and varied diatom flora 

 which includes, conspicuously, forms like Terpsinoe 

 musica, Biddulphia rhombus, Isthmia capensis, 

 Auliscus, Aulacodiscus, Navicula, and others. 



OTHER RECORDS 



Diatom records made in connection with oil- 

 pollution investigations conducted in Louisania 

 by the biologists engaged by oil companies and by 

 persons representing various conservation and 

 fishery interests have not been published and are 

 not generally available. They are probably rather 

 limited since these investigators have not been 



