148 Bulletin 29 312 



Locality. — (Exp'd '16) Bluff 3, Cercado de Mao. 



Turbonilla ( Chemnitzia) cercade?isis , n. sp. 

 Plate 25, Figure 13 



Shell very minute, resembling in for in and in the number of 

 whorls Guppy's T.plastica, but his shell is described as having 

 spiral striae and is therefore a Pyrgiscus; whorls six (in addition 

 to the large helicoid nucleus, flattened on the sides and a trifle 

 narrower below than above, giving a turriculate appearance to 

 the whole shell; ribs straight, seemingly ending at the periphery 

 of the last whorl but actually extending feebly beyond it; ribs 

 broad, those ornamenting the last whorl eighteen, and about the 

 same number are on the two whorls preceding the last; inter- 

 spaces between the ribs narrower than the ribs, smooth and pol- 

 ished; base of shell smooth. Length 2.5, diameter .60 mm. 



Locality. — (Exp'd ' 16) Bluff 3, Cercado de Mao; 



Turbonilla (Strioturbouilla) dominicensis Gabb 



Plate 25, Figure 14 



Turbonilla Dominicensis Gabb, Trans. Amer. Phil. Soc, vol. 15, p. 

 225, 1873. 



Shell small, long and very slender, whorls eleven, very 

 slightly convex, flattened at their centers; suture deep, with the 

 ends of the ribs somewhat projecting, giving the whorls a finely 

 coronate aspect; ribs straight, very slightly oblique, extending 

 only to the periphery of the body whorl or very weakly beyond ; 

 number of ribs on the last whorl about sixteen, on the penulti- 

 mate fourteen and fourteen also on the third whorl from the last; 

 spiral sculpture very fine, delicate, and regular between the ribs, 

 coarser and weaker on the base; inner lip showing no fold, col- 

 umella twisted. Length 6, diameter .9 mm. Slenderer than T. 

 ornata d'Orb. and the ribs do not extend over the base as in that 

 shell. 



Locality. — (Exp'd '16) Bluff 3, Cercado de Mao. 



