408 R. J. L. Guppy — West Indian Tertiary Fossils. 



Zeiostraca clavata, PI. XVIII. Fig. 16. 



Shell rather club-shaped, whorls smooth, flattened, the last form- 

 ing more than ^ ; spire acuminate, suture linear, scarcely impressed ; 

 aperture suboval, elongate, narrow above, dilated in front; peristome 

 simple, columella somewhat reflected and thickened. 



Pliocene, Trinidad. Allied to L. acuta 



Turritella planigyrata, PI. XYIIT. Fig. 5. 



Conic-cylindric, striate by fine spiral lines, whorls very slightly 

 convex, the later ones nearly flat ; aperture sub-quadrate. 



Miocene, Trinidad. A very distinct species, remarkable for its 

 almost entire want of ornamentation, and the flatness of its whorls. 



Vermetus trilineahis, PL XVIII. Fig. 12. 



Conic-cylindric, turreted, spire pointed, whorls flat, bearing three 

 narrow spiral keels ; lower whorls irregular ; suture distinct, linear 

 shallow. 



Pliocene, Trinidad. The young shell is not to be distinguished 

 from a small Turritella, but the subsequent growth supplies the 

 Vermetiform character. 



Triforis gidtata, PL XVIII. Fig. 27. 



Eeversed, cylindrical ; whorls about eight, zoned with three spiral 

 lines of small obtuse points which are connected spirally and longi- 

 tudinally by threads ; suture impressed ; base with three or four 

 strong striations ; aperture produced into a canal ; peristome pro- 

 duced, inner margin with a narrow defined callus. 



Pliocene, Trinidad. Allied to T. ventricosus, Grael. 



Solarium semidecussatum, PL XVIII. Fig. 14. 



Small, orbicular depressed, strongly decussate on the upper surface, 

 nearly smooth on the lower surface ; umbilicus deep, its margins 

 crenate and spirally striate. 



Pliocene, Trinidad. It is with some doubt that I refer this species 

 to the genus Solarium. 



Cancellaria scalatella, n. sp., PL XVIT. Fig. 4. 



Turreted, umbilicate, spirally striate by numerous close spiral 

 threads more elevated on the stout rounded longitudinal variciform 

 ridges, of which there are six or seven on a whorl. Suture very 

 deeply sunk. Whorls about seven, slightly rounded, angulate and 

 crowned above by the ridges. Aperture almost triangular, rounded 

 above, angular and formed into an obsolete canal anteriorly. Outer 

 lip sharp, grooved within. Inner lip continuous, thin, sharp, slightly 

 reflected and bearing two folds. Base angulate, perforated by a 

 small round umbilicus. 



Eelated to C. vnricosa, Brocchi (Miocene, Piedmont) ; but smaller, 

 and of somewhat stouter figure. The spiral striae are coarser, and 

 the peristome is finely grooved instead of being coarsely dentate 

 only. In C. varicosa the spiral strise are crossed by very fine 

 longitudinal ones, which do not exist in C. scalatella. The most 

 striking difference, however, is that the whorls are rounder, and the 



