EAST COAST MARINE SHELLS 



61 



shell; lateral teeth obsolete. Length 3 

 inches. 



Single valves, in the writer's 

 cabinet, were collected in Florida at San- 

 ibel and in Lake Worth. This shell is of- 

 ten confused with Macoma constricta. 

 PI. 22, Fig. 2, PI. 76, Fig. 2 

 East Florida southward from Lake 

 Worth; West Florida southward from 

 Sanibel; West Indies 



Family Semelidae 



Shell somewhat rounded, umbones 

 turned forward; fold upon posterior end; 

 two cardinal, two lateral teeth, the lat- 

 ter long and distinct in right valve; out- 

 side ligament short, inside one long and 

 oblique; pallial sinus well excavated, 

 rounded. 



Some of these mollusks live deep 

 In mud or sand, the powerful foot being 

 used for creeping. They have been observed 

 ascending the sides of a vessel after be- 

 ing captured. 



GENUS SEMELE Schumacher 1817 



SEMELE BELLASTRIATA Conrad. Surface cov- 

 ered with distinct radiating ribs and rath- 

 er strong concentric ridges; shell com- 

 pressed, anterior end the longer; color 

 yellow, ochre or purple, often rayed or 

 spotted with violet inside. Length 25 mm. 



It has been dredged in 19 fathoms 

 off Key West, Florida. Beach specimens 

 are infrequent at Sanibel. 



PI. 21, Fig. 4 



North Carolina to Gulf of Mexico 



and West Indies 



SEMELE PROFICUA Pulteney-. Shell slightly 

 longer than high, nearly equilateral; liga- 

 ment small and placed in escutcheon; lu- 

 nule in front of umbones; concentric growth 

 lines strong, sometimes elevated into ridg- 

 es giving a wrinkled appearance to surface; 

 color white, straw or purple, often varie- 

 gated. Length '60 mm. 



Specimens have been taken at Palm 

 Beach, Marco and Sanibel in Florida. 



PI. 23, Fig. 11 



Virginia to Gulf of Mexico; West 



Indies 



SEMELE NUCULOIDES Conrad. Shell ovate. 



convex; concentric lines very minute and 

 regularly placed; anterior extremity acute- 

 ly rounded; umbones near the posterior ex- 

 tremity; basal margin arcuate; lateral 

 teeth obsolete. Length 4.5 mm.; height 

 3 mm. diameter 1.5 mm. 



North Carolina to Gulf of Mexico; 

 West Indies 



SEMELE PURPDRASCENS Sowerby. Shell oval, 

 posterior end angled, anterior end rounded; 

 color usually light yellowish; umbones 

 purple; indistinct variegations of purple 

 upon surface also; interior often deep 

 purple; concentric lines moderately im- 

 pressed, radial lines of similar strength. 

 Length 40 mm. 



Fresh double specimens have been 

 taken by the writer in Lake Worth, Florida, 

 near the North Inlet. Single valves, 

 brilliantly colored, are not rare on the 

 shores of Hobe Sound where possibly it may 

 live. 



PI. 23, Fig. 12 



North Carolina to Gulf of Mexico; 



West Indies 



GENUS ABRA 'Leach' Lamarck 1818; 

 Syndosmya Recluz 1845 



Shell small, whitish, rather com- 

 pressed; posterior end shortest. 



ABRA AEQUALIS Say. Shell orbicular, a 

 little oblique, rather thin, white, scarce- 

 ly shining; minute concentric wrinkles near 

 margin and which become absent near um- 

 bones; no lateral teeth; one cardinal tooth 

 and a vestige of a second on left valve; 

 one cardinal tooth and a feeble one behind 

 in right valve. Length 10 mm., height 8 

 mm., diameter 4 mm. 



PI. 25, Fig. 10 



Connecticut to Florida; Texas 



ABRA LIOICA Dall. Shell small, thin, um- 

 bones prominent; growth lines faint; smooth 

 and shining; umbones nearest to posterior 

 end, opposite end rovinded; left valve with 

 one prominent cardinal and one small tooth 

 behind; right valve with two strong cardi- 

 nals; lateral teeth absent in both valves. 

 Length 7 mm. Depth range 14-860 fathoms. 



It has been reported upon the 

 shore at Captiva Island, Florida. 



