CREPTDULA. 125 



C, GLAUCA, Sa3'. PI. 36, fig. 9. 



Rather flat, with a sharp pointed apex, yellowish brown with 

 radiating rows of chestnut spots, interior dark chestnut brown, 

 more or less mottled or spotted, septum white, diaphanous. 



Length, -75 inch. 



Long Island Sound to North Carolina. 



The darker color and smaller size distinguish this from 

 the preceding species, but I am not at all sure that it is more 

 than a varietal state of the young shell. Reeve's figure probably 

 represents a colorless G.fornicata. 



C. coNVEXA, Say. PI. 36, fig. 10. 



Convex, with somewhat trigonal outline, high back and ob- 

 liquely beaked apex ; whitish or glaucous radiately lined with 

 chestnut spots, with sometimes larger nebulous chestnut-purple 

 markings. Length, "75 inch. 



Nova Scotia to Florida. 



The form of this species is due to its attachment on the crus- 

 tacean Eupagurus longicarpus and the gastropod Ilianassa 

 obsoleta. The preceding species has been supposed identical 

 with this, and simpl}' modified b}- attachment to broad flat sur- 

 faces ; this msij be so, yet the present is a smoother, lighter-colored 

 heavier shell. Its identity with Cfornicata is not improbable. 

 C. navicula (Dunker), Morch;a West Indian form, insufficiently 

 described, and unfigured, is probably a synonym. 



C. ADSPERSA, Dunker. PL 36, figs. 11,12. 



Ovate, more or less convex, rugulose, white with chestnut 

 spots, epidermis olivaceous. Length, 1 inch. 



Benguela. 



Possibly a form of the last species. 



C. LENTiGiNOSA, Sowb. PI. 36, figs. 13, 14. 



Yellowish chestnut-colored, with purple chestnut radiating 

 series of spots. Length, 1 inch. 



Cape of Good Hope. 



Perhaps identical with G. convexa, Say, and the last species. 



C. Capensis, Quoy. PI. 36, figs. 15, 16. 



Suborbicular, flattened, radiately, obsoletely striated, chestnut- 

 brown, brighter colored within. Length, 1*25 inches. 



Cape of Good Hope. 



