290 PUPILLID-I. 



Benson states * that it has more affinity with Ballmus. In one 

 of the two specimens received by him the parietal hxmina was 

 not apparent. I have not seen specimens, but to judge from the 

 figure in Conch. Ind. neither Blanfoi'd nor Benson appears to me 

 to have been happy in their comparison, as salemensis seems much 

 nearer to brevicostis. 



Genus BIFIDARIA, SterJci. 



Bijidaria, Sterki, Nautihis, vi, 1892, pp. 4, 99 (as subgenus of Pupa) ; 

 Pilsbry, Proc. Acad. Nat. Sci. Philadelphia, 1900, p. 590 (as genus 

 oi Pupidce). 



Type, (1st species) Pupa hordeacea, Gabb. 



Range. North and Central America, North Coast of South 

 America, West Indies, Bermudas, Eastern Asia, Islands of the 

 Pacific and Indian Seas. 



Shell small, few exceeding 3 mm. in height, varying in shape 

 from cylindric and turriculate, to conic and ovoid. Colour 

 lighter or deeper corneous, chestnut or whitish. Surface smooth, 

 polished, finely striate, or with fine ribs. Parietal lamella more 

 or less complex, composed of a parietalis — inner — and supra- 

 parietalis — outer, or angular — almost separate, side by side in 

 some species, united to almost a simple one in others, com- 

 paratively small in some, the supraparietal very small or almost 

 obsolete in others. The coluuiellar lamella, equally constant, is 

 generally also somewliat complex. Typical inferior and superior 

 palatal plicae always present, sometimes quite small, as a rule 

 deep-seated, never reaching the margin ; in some species one 

 or the other is in a peculiar oblique position. Generally, but not 

 always, there is a tootli or short fold at the base. In many 

 species additional dentiform or lamelliforin plicae, sometimes veiy 

 small, are found ; one on the ])arietal wall, between the parietal 

 and the columella, constant or inconstant, one above the upper 

 palatal, one between the two palatals, inconstant. {Sterki.) 



259. Bifidaria bathyodon, Benson. 



Pupa bathyodon, Benson, A. M. N. H. ser. 3, xii, 1863, p. 426 ; 



Pfeiffer, Men. Helic. Viv. vi, 1868, p. 326; Hanley & Theobald, 



Conch. Ind. 1874, pi. 100, fig. 7 ; Sowerby, Conch. Icon, xx, 1876, 



Piqxc, pi. 4, fig. 33, pi. 16, fig. 152. 

 Ptipa (Scopelophila) bathyodon, Nevill, Hand List, i, 1878, p. 192. 

 Piqm {Pupilla) bathyodon, Pfeiffer & Clessin, Nomencl. Helic. Yiv. 



1881, p. 355. 



Original description : — " P. testa profunde rimato-perforata, 

 ovato-conica, oblique striatula, fusco-cornea, translucente ; spira 



* A. M. N. H. ser. 3, xii, 1863, p. 428. 



