62 



EAST COAST MARINE SHELLS 



PI. 23, Fig. 13 



PI. 62, Fig. 8 



North Carolina to the West Indies 



GENUS COMINGIA Sowerby 1833 



Shell gaping and pointed behind; 

 concentrically laminated. 



COMINGIA TELLINOIDES Conrad. Surface diall 

 except region of umbones, white or yellow- 

 ish; two lateral teeth very long; two car- 

 dinal teeth small and with cup-shaped de- 

 pression between them; concentric lines ir- 

 regular and rather prominent. Length 14 

 mm. 



PI. 23, Fig. 6 



Cape Cod to Gulf of Mexico; West 



Indies 



COMINGIA COARCTATA Sowerby. Shell oval, 

 concentrically lamellated; anterior end 

 high, rotiind; margin dorsally declining. 

 Often found in sponges. Length 80 mm. 



These two Cumingias are apparently 

 of common descent, the young being almost 

 identical. 



PI. 23, Fig. 5 



Florida Keys and West Indies 



Family Donacldae 



Shell wedge shaped, closed; poste- 

 rior end produced, more or less rounded, 

 anterior end short and straight; edge usu- 

 ally crenulated; ligament external; um- 

 bones pointing backward. 



The Donacldae live in clean sand 

 upon the ocean beaches. 



GENDS DONAX Llnn6 1758 (WEDGE SHELLS) 



DONAX DENTICDLATA Linn^. Toothed Wedge. 

 Shell solid, long triangular; anterior end 

 narrow and rounded; base line a little 

 curved and with faint angulation in center; 

 fine radiating ridges on surface, peculiar- 

 ly serrate on their edges; strong oblique 

 ridges on posterior slope, with fine 

 threads between them; inner margin of 

 shell toothed; palllal sinus deeply im- 

 pressed. Length 28 mm. 



The color range is considerable. 

 Yellow, brown and violet tinted shells oc- 

 cur, often beautifully rayed. It is a com- 

 mon shell in the West Indies. 



PI. 25, Fig. 3 



Florida Keys; Texas; West Indies 



DONAX FOSSOR Say. Digging Wedge. Often 

 an olive-colored shell with bluish rays. 

 Posterior end rounded; sides not angular; 

 radiating sculpture covered by a thin lay- 

 er so that surface of shell is smooth. A 

 slight magnification shows the radiating 

 lines. This species is thinner than D. 

 variabilis with consequent smaller crenu- 

 lations upon the margin. Length 12-15 mm. 



It is the most plentiful shell on 

 the New Jersey coast. Johnson reports "At 

 Anglesea I once saw them washed out of the 

 sand in pools around the stanchions of a 

 wrecked vessel, almost a bushel of living 

 shells being present in each pool." Wood 

 recounts the results of a quantitative 

 study, counting one thousand five hundred 

 and ten live Donax in one square foot. 

 These were in Cape May Coionty, New Jersey. 



PI. 10, Fig. 12 



Long Island, New York to Florida 



Keys 



DONAX TOMIDA Philippi. (D. obesa Orb.). 

 Inflated wedge. Shell small, very stout, 

 polished, more rounded than D. variabilis, 

 shell also more Inflated; striae only vis- 

 ible under a glass. Length 10-12 mm. 



PI. 10, Fig. 9 



St. Augustine, Florida, to Texas 



DONAX VARIABILIS Say. Variable wedge. 

 Posterior end obliquely truncate, the sides 

 decidedly angular; the little ribs with 

 interspaces of almost equal width being 

 plainly visible to the naked eye. Length 

 20-25 mm. 



This, the commonest east coast 

 wedge shell occurring In the south, is of- 

 ten used in the preparation of broth. 

 There are almost countless color combina- 

 tions on the shells. 



PI. 25, Fig. 10 



Cape Hatteras, North Carolina to 



Texas; West Indies 



GENDS IPHIGENIA Schumacher 1817 



Shell almost equilateral; two 

 hinge teeth in each valve, one bifid, the 

 other minute; lateral teeth far apart, ob- 

 solete in left valve; margins smooth. It 

 inhabits estuaries and quiet brackish water. 



