56 Bulletin 29 220 



varix behind it; canal short, reflexed. Length of shell 13.5, 

 greatest width 5 mm. 



Locality. — (Exp'd '16) Zone D, Rio Gurabo near Los Que- 

 mados. 



Drillia maonisriparum, n. sp. 



Plate 9, Figure 5 



Shell with three nuclear whorls, the first two smooth, the 

 third ribbed; post-nuclear whorls five, separated by a linear su- 

 ture, beneath which is a prominent spiral ridge forming the up- 

 per border of the sub-sutural channel; the latter is marked by 

 arcuate growth-lines and several fine spiral threads; below the 

 sub-sutural channel the whorls are sculptured by about fifteen 

 rather sharp, straight, longitudinal ribs, several of which may be 

 replaced on the body whorl by a single rounded varix; in the 

 interspaces between the ribs are numerous spiral threads which 

 cross the varix but not the crests of the ribs; the spirals extend 

 to the base of the shell but the ribs terminate below the convex- 

 ity of the body; outer lip sharp; posterior sinus deep, small, cir- 

 cular. Length 9.5, width 4 mm. 



Localities. — (Exp'd '16) Bluff 2 (rare), Bluff 3 (fairly com- 

 mon), Cercado de Mao. 



Drillia hispaniolce \ n. sp. 

 Plate 9, Figure 6 



Shell small, slender, graceful, with eight whorls, the first 

 two smooth nuclear, post-nuclear whorls six, ornamented by 

 close, rounded, slightly arcuate, longitudinal ribs of which there 

 are twelve and a rounded varix on the last whorl; the ribs stop 

 short at the anterior edge of the narrow sub-sutural channel, 

 which is bordered on its posterior edge by an inconspicuous 

 spiral ridge; spiral sculpture of equal, equidistant threads which 

 cross the crests of the ribs as well as the interspaces and varix ; 

 posterior sinus deep, narrow, U-shaped; outer lip sharp. Length 

 9.5, width 3.25 mm. 



