EAST COAST MARINE SHELLS 



147 



smooth; grayish with brovm bands; whorls 

 ten; aperture narrow, angular, lip acute. 

 Length 7.5 mm. 



PI. 55, Fig. 5 



PI. 67, Fig. S 



Tampa Bay, Florida to Florida Keys 



GENUS DETRACIA Gray 1840 



DETRACIA BULLOIDES Montagu. Shell heavy, 

 thick, shining, brownish with white revolv- 

 ing bands; whorls ten, tapering toward 

 base; six to eight elongated ridges inside 

 but not quite reaching outer lip. Length 

 11 mm. 



On Big Pine, one of the lower Flor- 

 ida keys, Detracia lives under stones and 

 bits of wood not far from the ocean beach. 



PI. 55, Fig. 1 



PI. 67, Fig. 7 



Cedar Keys, West Florida to Florida 



Keys 



GENUS SAYELLA Dall 1885 



SAYELLA CROSSEANA Dall. Length 2.5 mm. 

 PI. 67, Fig. 10 

 Egmont Key, Florida; West Indies 



SAYELLA HEMPHILLII Dall. Length 3.75 mm. 

 PI. 67, Fig. 11 

 Cedar Keys, Florida 



GENUS BLAQNERIA Shuttleworth 1854 



BLAUNERIA HETEROCLITA Montagu. 

 PI. 67, Fig. 14 

 Tampa, Florida to West Indies; 

 Europe 



Family Piliidae 



The "apple snails" are fluviatile. 

 The breathing cavity being partly closed 

 they are able to remain out of water for 

 long periods, even years in times of drought. 



The animal's tentacles are long, 

 the lips so modified that they resemble an 

 additional pair of tentacles. On the left 

 side of the mantle is a long siphon; large 

 pulmonary sac on each side of mantle cavity; 

 operculum usually completely closing aper- 

 ture. 



In the mightiest of rivers sucn as 

 the Amazon and its tributaries, the Ganges, 

 and the Nile, live the largest and finest 

 species. A South American bird has a beak 

 especially designed for entrance under the 

 operculum of a Pomacea. 



GENUS POMACEA Perry 



All of the species which inhabit 

 the Western Hemisphere are provided with a 

 horny operculum and are placed under this 

 genus . 



POMACEA PALUDOSA Say. Spire of shell much 

 depressed, whorls four, pale olive or brown 

 with greenish or brownish lines. Length 

 1.5 inches. 



This fresh-water snail apparently 

 lives in every Florida county. It prefers 

 a muddy station and a sluggish stream or 

 pond. At night it is most active and shoxild 

 be sought for with a flashlight. The writer 

 observed a large number of adolescent indi- 

 viduals living under water hyacinths in the 

 St. John's River near Orange, Florida. In 

 Volusia County it also occurs plentifully 

 as a fossil in the shell-gravel pits, the 

 material from which is used as a top dress- 

 ing for minor roads. Large numbers of dead 

 and bleached specimens may be seen upon the 

 banks of canals throughout the state and 

 elsewhere In the south. The eggs are shown 

 in Fig. 52. 



PI. 57, Fig. 13 



South Carolina to Louisiana 



Fig. 52 

 Eggs of Pomacea 



POMACEA PALUDOSA FLAVA Pilsbry. A striking 

 yellow shell, without bands. This variety 

 has been collected in canals near Plnecrest 

 on the Tamiami Trail. 



Central Everglades and near Miami, 



Florida 



