472 



FISHERY BULLETIN OF THE FISH AND WILDLIFE SERVICE 



Macrocallista maculata Linn6. 

 Chione cancellata Linn6. 

 Donax variabilis Say. 



3. Brackish water estuaries : 



This habitat is found all along the shores of 

 the Gulf of Mexico. The mollusks listed here 

 are found both on sandy and muddy bottom as 

 well as on rocky substrata and on objects such as 

 jetties and pilings. 



Neritina reclivata Say. 

 Batillaria minima Gmelin. 

 Cerithidea scalariformis Say. 

 Congeria leucophaeata Conrad. 

 Cyrenoida fioridana Dall. 



4. Mangrove flats : 



A few species are foimd predominantly in this 

 habitat. 



Littorina angulifera Lamarck. 

 Cypraea zebra Linn6. 

 Isognomon alatum Gmelin. 

 Oslrea floridensis Sowerby. 



CAROLINIAN PROVINCE 



This area extends from Cape Hatteras, North 

 Carolina, south to about Cape Canaveral on the 

 east coast of Florida, and from about Tampa Bay 

 on the Florida west coast northward and west- 

 ward along the shore of the Gulf to about 

 Corpus Christi Bay, Texas. Some elements of this 

 faima on the western side of the Gulf may go 

 farther south into Mexico, while some tropical 

 forms may reach the vicinity of Matagorda Bay. 



The shores of this area have a rather uniform 

 character, without coral reefs or mangrove vege- 

 tation. Instead we have mile on mUe of sandy 

 beaches, often along low coastal islands, behind 

 which are lagoons, bays, and estuaries with vary- 

 ing degrees of salinity. Frequently we find oyster 

 reefs on the lagoons and bays, but outside of these 

 oyster banks the only soUd substrata are mainly 

 in the form of man-made structures such as 

 jetties and pilings. 



This province may conveniently be subdivided 

 into the foUowing ecological areas: 



1 . Outer sandy beaches and nearshore sandy areas : 



Epitonium angulatum Say. 

 PoHnices duplicata Say. 

 Sinum perspectivum Say. 

 Strombus pugilis alatus Gmelin. 

 Chicoreus fulvescena Sowerby. 

 Busycon spiratum plagosum Conrad. 

 ~>liva sayana Ravenel. 



■'a-^a campechiensis Gmelin. 



Anadara brasiliana Lamarck. 

 Noeiia ponderosa Say. 

 Trachycardium muricatum Linn4. 

 Dinocardium robuslum Humphrey. 

 Laevicardium mortoni Conrad. 

 Dosinia discus Reeve. 

 Macrocallista nimbosa Humphrey. 

 Tellina alternata Say. 

 Tellina versicolor DeKay. 

 Donax variabilis Say. 

 Tagelus gibbus Spengler. 

 Barnea costata Linn6. 



2. Bays and lagoons, moderate to high salinity, 



sandy or muddy bottom: 

 Cerithium variabile C. B. Adams. 

 Nassarius acuta Say. 

 Nassarius vibex Say. 

 Acleocina canaliculata Say. 

 Pecten gibbus amplicostatus Dall. 

 Volsella demissus granosissimus Sowerby. 

 Chione cancellata Linn6. 

 Mercenaria mercenaria Linn6. 

 Abra aequalis Say. 

 Mulinia lateralis Say. 

 Ensis minor DaU. 



3. Bays and lagoons, brackish water: 



Neritina reclivata Say. 

 Littorina irrorata Say. 

 Polymesoda carolinensis Bosc. 

 Rangia cuneata Gray. 



4. Jetties and oyster reefs in bays: 



Crepidula plana Say. 

 Thais fioridana Conrad. 

 Anachis obesa C. B. Adams. 

 Brachidontes recurvus Rafinesque. 

 Crassostrea virginica Gmelin. 



DEEPER WATERS OF THE GULF OF MEXICO 



In these deeper waters we find many species 

 that show a relationship with the tropical element 

 of the Caribbean area. We have, for instance, 

 Terebra taurinum Humphrey (Jlammea Lamarck) 

 and Sconsia striata Lamarck which extend into 

 the West Indies. Others are peculiar to the Gulf. 

 The explorations that are now going on in the 

 Gulf of Mexico and future dredgings will un- 

 questionably bring to light many more new and 

 interesting forms. 



Gaza superba Dall. (W) 



Murex beaui Fischer and Bernardi. (W) 



Oocorys bartschi Rehder. (G) 



Fusinus couei Petit. (G) 



Scaphella junonia Shaw. (G) 



Conus sozoni Bartsch. (G) 



Polystira albida Perry. (W) 



Polystira tellea DaU. (G) 



