278 GENUS POLYGYRA. (June, 



are much more conspicuous near the mouth; mouth sub- 

 reniform, two projecting, obtuse teeth on the outer Hp 

 within, separated by a deep sinus; outer Up elevated, equal, 

 describing two- thirds of a circle; pillar lip elevated, 

 broadly but not profoundly emarginate, concave beneath, 

 and connected by the inner side to an elongated lamelli- 

 form tooth, which is placed obliquely on the penulti- 

 mate whorl, near the middle of the mouth; lips almost 

 equally prominent, continued; umbilicus moderate, not 

 exhibiting the volutions, no groove on the ultimate 

 whorl within it. 



Breadth one fourth of an inch. 

 Inhabits Florida. 

 Cabinet of the Academy. 



Animal longer than the breadth of the shell, acute 

 behind, above granulated and blackish, beneath, and 

 each side, white. 



This we found in the orange gi'oves of Mr. Fatio,|on 

 the river St. John, East Florida; it is usually covered 

 with a black, earthy coat, which is probably collected 

 and detained by the hairs. When unincumbered with 

 this vesture, the shell is of a horn colour. It is by no 

 means so common as the preceding species. 



3. P. ^septemvolva. Shell much depressed, discoid 

 dal; spire not prominent; whorls seven, perfectly lateral, 

 compressed, depressed, and marked with conspicuous 

 lines and grooves above, a projecting carina on the up- 

 per edge of the body whorl, beneath which the lines and 

 grooves are obsolete; aperture subreniform, not contract- 

 ed; lips equal, elevated, outer one reflected, regularly 

 rounded so as to describe two- thirds of a circle, pillar lip 

 projecting inwards, into an angle or tooth, which is con- 



