46 BULLETIN OF THE 



over and turning forward to meet a carina which revolves about the apex ; 

 apex truncate, carinated by a line which forms the outer boundary of the path 

 of the notch, within vorticiform, about one and a half whorls visible around 

 the central perforation and descending into it; body with hardly any wash 

 of callus; pillar strong, with a large horizontal fold and a minute chink behind 

 it ; aperture as long as the shell, straight and narrow behind, wide and some- 

 what oblique in front ; max. Ion. of shell, 5.0 ; max. lat. 3.0 ; lat, of apex, 

 1.75 mm. 



Habitat. Station 20, off Bahia Honda, Cuba, in 220 fms., bottom tempera- 

 ture 62°.0. Barbados, 100 fms. 



It is difficult, or rather impossible, to determine the generic place of these 

 small Tectibranchs without a knowledge of the soft parts. They are referable 

 to Coleophysis, Cylichna, or Diaphana, or even Sao, at the option of the de- 

 scriber, guided only by tlie characters of the shell. The presence of the plait 

 would indicate the first-mentioned section for the present species. It is per- 

 haps nearest in general form to the Cylichna ovata of Jeffreys, or Diaphana 

 gemma of Verrill, which has no plait and is much more attenuated behind. 



Subgenus CYLICHNELLA Gabb. 



Cylichnella bidentata Orbigny. 



Bulla bidentata Orbigny, Moll. Cuba, I. p. 125, pi. iv. figs. 13-16, 1841. 



Bulla biplicata Lea, Proc. Bost. Soc. Nat. Hist., I. p. 204, 1844 ; Journ. Nat. Hist., 



V. p. 286, pi. xxvi. fig. 2, 1847. 

 Utriculus biplicatus Tryon, Am. Mar. Conch., p. 104, pi. xiii. fig. 213, 1873. 

 Cylichnella bidentata Gabb, Proc. Phila. Acad. Nat. Sci., p. 273, pi. x. fig. 2, 1872. 



Geol. San. Domingo, p. 246, 1873. Morch, Malak. Blatt , XXII. p. 171, 1875. 

 Cylichna biplicata Bush, Hatteras Moll., Trans. Conn. Acad., VI. p. 467, pi. xlv. 

 fig. 14, 1885. 



Habitat. From Hatteras to Santo Domingo in 7-168 fms., and from Florida 

 to Texas near low- water mark. Barbados, 100 fms. 



Miss Bush may have been right in referring this to Cylichna, which it much 

 resembles, but I cannot help thinking it should be placed in this family. 

 Cylichna oryza Totten belongs in the same subgenus, but is more inflated and 

 larger. This is not the Cylichna biplicata Adams described in 1850 from the 

 Chinese Seas. 



Genus UTRICULUS (Brown) Adams. 



Utriculus Mayoi Dall. 



Shell solid, white, with a yellowish polished epidermis and well marked 

 lines of growth, spiral striae very faint and few, or none ; whorls 3^-4, spire 

 distinct, little elevated, nucleus small, rounded, not prominent ; aperture 



