ATYS. 275 



A. guildinii Sows., Conch. Icon, xvii, pi. 5, f. 26. 



Seems more pyriform than A. caribcea. Sowerby probably in- 

 tended the name as an allusion to that clear-seeing pioneer, GUILD- 

 ING ; but in this case, as in so many others throughout his mono- 

 graph, the performance fell short of the good intention. 



A. SPECIOSA A. Adams. PL 28, fig. 42. 



Shell oval, perforated, posteriorly narrowed and subtruncated, 

 anteriorly rounded and ventricose, white, semiopaque, shining, lon- 

 gitudinally superiorly strongly striated, inferior striae evanescent, 

 transversely striated at both ends ; outer lip thickened within, pos- 

 teriorly twisted, with a single plait ; inner lip reflexed, anteriorly 

 semiplicated (Ad.}. 



Habitat unknown. 



B. (JL) speciosa A. AD., Thes. p. 587, pi. 125, f. 122. SOWB., C. 

 Icon. t. 3, f. 14. 



A. RIISEANA Dunker. Unfigured. 



Allied to Bulla cylindrical Helbl., but much smaller. Alt. 10, 

 diam. 5 mill. (Jforc/i). 



St. Thomas (Riise, Ravn.) ; St. Martin ; New Providence ; Trini- 

 dad; Anguilla ; Porto Plata (Krebs). 



Atys riiseana Dkr., MSS., MORCH., Mai. Bl. xxii, p. 173. 



This does not seem to be different from A. caribcea. 

 A. SANDERSONI Dall. PL 28, fig. 47. 



Shell small, thin, fragile, polished, translucent-white, with the 

 aperture longer than the axis of the shell, slender, elongated oval 

 with the posterior fourth bevelled off slightly ; transverse sculpture 

 solely of delicate evanescent lines of growth, sometimes lost in the 

 general polish of the surface ; spiral sculpture of about a dozen in- 

 cised lines near either extremity, more crowded toward the tips and 

 obsolete toward the middle of the shell, reticulating the lines of 

 growth when the latter are present, but delicate, extremely fine, 

 and not puncticulate ; posterior apex a rather deep funiculate pit, 

 from the center of which rises the margin of the aperture, which is 

 here slightly reflected, extends behind the summit of the body and 

 suddenly curves forward, leaving a very narrow aperture, which is 

 produced into a rounded point in front, then sharply recurved and 

 reflected to a point where the reflected part loses itself in the thin 

 callus on the body within the aperture ; the anterior reflection is 



