EAST COAST MARINE SHELLS 



47 



cancellate ornamentation by the intersec- 

 tion of the concentric lamellae and weaker 

 radial threads. The posterior slope is 

 weakly depressed in front of the margin. 

 Length 4-6 mm. Depth range 2-124 fathoms. 



PI. 23, Fig. 14 



Cape Henry, Virginia to Cuba 



SECTION BELLUCINA Dall 1901 



LUCINA AMIANTUS Dall. Shell small, solid, 

 white; about twelve strong low ribs which 

 are crossed by strap-like threads; inner 

 margin finely crenulate. Length 6 mm. 

 Depth range 2-640 fathoms. 



This is an extremely elegant lit- 

 tle shell and can hardly be confused with 

 any other. First found on the west coast 

 of Florida it has since turned up in scat- 

 tered localities. 



PI. 15, Fig. 5 



Cape Lookout, North Carolina to 



West Indies 



GENUS DI VARICELLA V. Martens 1880 



Somewhat rounded semi-glossy shells 

 with peculiar sculpture. 



DIVARICELLA DENTATA Wood. Larger than D. 

 quadrisulcata, also distinguished by the 

 toothed dorsal margin and the lateral 

 teeth inside the shell. There is a tenden- 

 cy in old individuals toward obsolescence 

 of these, particularly the lateral teeth. 

 The small and deep Ixmule is present in all 

 ages. Diam. 1.5 inches. It lives in 10- 

 50 fathoms but single valves sometimes are 

 found on the beaches. 



PI. 16, Fig. 4 



PI. 73, Fig. 6 



North Carolina to West Indies 



DIVARICELLA QUADRISULCATA Orbigny. Shell 

 white, surface glossy, sculptured with 

 grooves bent obliquely downward at both 

 sides; lateral teeth obsolete; margin of 

 shell toothed, hinge margin almost straight; 

 one very small tooth in right valve, two 

 small diverging ones in left; ligament al- 

 most concealed. Length 1 inch. 



Found on every Atlantic shore and 

 remarkable for its wide dispersion; also 

 frequent in fossil form. Range 10-50 fath- 

 oms. Much commoner upon beaches than the 

 preceding species. 



PI. 16, Fig. 5 

 Massachusetts to Brazil 



GENUS CODAKIA Scopoli 1777 



Shell large and heavy with more or 

 less reticulate siirface sculpture; exteri- 

 or white; color, when-present, chiefly up- 

 on interior and near margins. 



CODAKIA ORBICULARIS Linnfe. Shell large, 

 rather solid, narrov/ sharp umbones; numer- 

 ous radiating ribs or narrow furrows which 

 cut the surface into ridges of varying 

 widths; growth lines elevated making sur- 

 face cancellated; color whitish or yellow- 

 ish, often touched with purple on border, 

 chiefly above. Length 80 mm. 



Very abundant on sandy bottom at 

 depth of a foot or so, or among algae in 

 the Florida Keys. A very fine species. 



PI. 19, Fig. 5 



Florida; Gulf of Mexico; West 



Indies 



SUBGENUS JAGONIA Recluz 1869 



CODAKIA OREICULATA Montagu. Shell of mod- 

 erate size, covered with rather broad ra- 

 diating ribs, concentric lines not so strong, 

 often with several growth and rest lines; 

 limbones nearest anterior end; shape oblique, 

 moderately impressed; hinge inconspicuous; 

 lunule large and wedge shaped; two pointed 

 lateral teeth in each valve. Length 13 mm. 



Dredged in shallow water of Barnes 

 Sound, Florida. 



PI. ,15, Fig. 6 



PI. 14, Fig. 8 



North Carolina; Florida; Vilest 



Indies 



CODAKIA COSTATA Orbigny (L, antillara Rve.). 

 Large and small radial ribs alternating or 

 in pairs; concentric sculpture least promi- 

 nent; lionule well impressed, narrow, almost 

 heart-shaped; muscle scar not deep, pallial. 

 line narrow. Length 13 mm. Depth range 

 13-85 fathoms. 



PI. 15, Fig. 9 



North Carolina to Brazil 



GENUS LORIPINUS Monterosato 1883 



LORIPINUS CHRYSOSTOMA Phillppi. Shell 

 large and recognizable by its "mellow 



