50 ^Fr. K. .1. L. Oui.py on 



anteriorly somewhat produced and suban^ular ; ])osteriorly 

 hij^h, with a decided obtuse angle formed by a low keel 

 runninc: from the umbo, on the u])])er and ]iosterior side of 

 which koel the shell is covered with a black i^j)iderniis. Valves 

 flattened, white, rather frairile, marked with concentric strias 

 of growth, which are worn smooth on the disk and umboncs, 

 but towards the ventral margin are covered with a yclli)wish- 

 brown wrinkled epideniiis. Length 85 millims., height 60, 

 thickness 30. 



Closely allied to .V.frof/ih's, which, indeed, appears to have 

 been confounded with it. The details of the hinge are some- 

 what similar to those of the hinge of Ifemimncfra f/i<janfea j 

 but the postcarinal area resembles that of Schizodesma. The 

 latter feature is much developed in our shell, and is remark- 

 able for its black epidcmiis, that of the other portions of the 

 shell beine: of a liirht brown. 



VII. — Xof ice of some Marine Shells found on the Shores of 

 Trinidad. By R. J. Lechmere Guppy, F.L.S., F.G.S., &c. 



[Plate VII. figs. .3 & 4.] 



Pwjnira trinitatensisj Guppy. 



A solid, ovate, yellowish, subrimate shell, adorned with 

 numerous rounded spiral ridges, which are crossed by fine 

 imbricating striae : whorls about 6, with four spiral rows of 

 obtuse elongated tubercles, of which the two nj)per rows are 

 much the largest, the superior one forming the angle of the 

 whorls : suture hidden by a row of stout curved and reflected 

 lamellae, of which there are about three above each of the 

 tubercles on the angle of the whorl : spire conic, sharp : 

 mouth pink within, and often ornamented with two or three 

 more or less interruj^ted spiral red or chestnut lines correspond- 

 ing to the external rows of tubercles : aperture oval, with a 

 small and decided posterior canal forming the successive sutural 

 lamelljE ; anterior canal open and a little reflected : pillar-lip 

 smooth, flattened or hollowed out, bright pink ; outer lip den- 

 ticulate, obsoletely striate Avithin. Height 40 millims., greatest 

 breadth 27, longest diameter of aperture 26. 



Hah. Gulfof Paria. 



A specie:5 somewhat resembling P. mancineUa, but with a 



sharper spire and a more decided striation. The sutural 



lamelloc are well develo]»ed, like those of P. coronaia. There 

 is a strong:' idge round the base. 



