556 



MOLLUSCA 



M. pomum Gmelin (Fig. 871). Length 12 cm.; color yellowish- 

 brown; surface rougli; aperture round and yellow in color, the outer 



lip having 3 brown spots: Beaufort, N. C, 

 and southwards; West Indies; common. 



2. XJrosalpinx Stimpson. Shell fusi- 

 form, surface roughened by about 12 

 rounded, longitudinal ridges; lip scalloped; 

 aperture with a short canal: 20 species. 



E. cinereus (Say). Oyster drill (Fig. 

 872). Shell 25 mm. long, 15 mm. wide, 

 brown or gray in color, brownish within; 

 whorls 5 or 6, with numerous revolving lines 

 which cross the longitudinal ridges : Florida 

 to Massachusetts Bay, and locally further 

 north, also at San Francisco; very common 

 on oyster beds, being one of the worst ene- 

 mies of the oyster, which it kills by drilling 

 a small round hole through the shell, through 

 which it thrusts its long proboscis. 

 3. EXTPLEURA Adams. Shell fusiform; surface roughened by about 

 10 longitudinal ridges; whorls 7 and angulated, there being a shoulder 

 beneath the suture: 5 species. 



E. caudata (Say) (Fig. 873). Shell 25 mm. long, 15 mm. wide, 

 brown or gray in color; aperture oval, with a long straight canal; lip 



Fig. 871 



Murex pomum (Rogers), 



1, slphonal canal. 



Fig. 872 



Fig. 873 



Fig. 874 



Fig. 872 — Urosalpinx cinereus (Verrill). 1, siplional canal. Fig. 873 — Eupleura 

 caudata (Verrill), Fig. 874 — Purpura lapillus (Verrill). 



thick, roughened within: Cape Cod to west Florida, in shallow water; 

 rather common. 



4. Purpura Bruguiere. Shell oval, lowest whorl large, with a large 

 aperture, the canal being reduced to a notch at its lower end; columella 

 flattened; outer lip simple: 60 species; cosmopolitan; several species. 



P. lapillus (L.) (Fig. 874). Shell thick, with 5 or 6 whorls; spire 

 acute; whorls with deep revolving furrows; lip arched, with ridges 



