GASTEROPODA. 133 



I cannot say. There is nothing in our shell like the holes represented in the 

 enlarged portion of his figure ; I have therefore left it for the present with the 

 name given to it in my Catalogue, until it can be correctly determined by a 

 comparison with the Mediterranean specimens. 



17. Teochus obconicds. S. Wood. Tab. XIV, fig. 10, a — d. 



Tuocuus obconicus. S. Wood. Catalogue 1842. 



. i 



Tr. Testa pusittd, orbiculato-conoided perforata; apice obtuso ; anfractibus quatuor, 

 super ne planulat is, subtus convexis ; transversim lineatis, lineis elevatis, crenulatis ; suturis 

 prqfundis, subcanaliculatis ; umbilico parvo. 



Shell small, obconical ; apex rather obtuse ; whorls somewhat flat above, convex 

 beneath, with transverse crenulated lines or striae ; suture deep, subcanaliculated ; 

 aperture obtusely quadrate, and a small umbilicus. 



Axis, y of an inch. 



Locality. Cor. Crag, Sutton. 



This is an abundant shell, and my specimens are all from one locality. In 

 general the transverse lines are regular in distance, and are about eight in number, 

 crossed by elevated and imbricated lines of growth, which give the exterior a 

 crenulated appearance ; the lines being prominent, particularly the upper and 

 lower ones, produce an apparent canal at the suture. In some specimens there 

 are only four elevated lines, var. /3, fig. a — b. The base is convex, with about 

 eight spiral lines ; there is a small umbilicus, and the shell is nacreous. It is pos- 

 sible this may be Tr. crispulus, Phil., but my specimens have not the rounded 

 volutions of that shell as represented in his figure (t. 25, f. 12). 



18. Trochus ditrohs. S. Wood. Tab. XIV, fig. 9, a—b. 



Trociius bic.viunifekus. S. Wood. Catalogue 1842. 



Tr. Testa minutd, orbiculato-conicd, perforata ; spird depressd ; anfractibus 3 — 4, 

 rotundatis, bicariniferis; transversim striatis, et tenuissime imbricatis; aperturd orbiculato- 

 quadratd ; umbilico parvo prof undo . 



Shell small, orbiculato-conical, striated along the volutions, and very finely 

 imbricated across them ; whorls round, convex beneath, with two sharp and promi- 

 nent keels ; aperture subquadrate ; umbilicus rather small, and deep. 



Axis, ^ of an inch. 



Locality. Cor. Crag, Sutton. 



This pretty little shell is not very abundant, and I have as yet seen it but from 

 one locality. The volution bears two elevated and sharp carinas, dividing it into 

 three unequal parts ; the spaces above and beneath being wider than that between 

 the keels ; but, as the volution joins the lower keel, one carina only is visible upon 

 the spire. The transverse or spiral strias are broad and flat ; about half a dozen 



