with a revision of thè LimnmidcB of Authors. 353 
« 
Genus Pompholyx. Lea. 1856. 
Tentacles medium, stout, eylindrical, slightl_y globose at thè 
tips. Genitalia on thè left side. Teeth (See figure I.). 
Shell few-whorled, last whorl ventricose. Aperture oblique, 
obtusely angulate below, eutire. 
Type Pompholyx effusa. Lea. 
Genus Choanomphalus. Gerstfeldt.'* 1860. 
Animai unknown. 
Shell deeply umbilicate, resembling Tropidina. 
Type Choanomphalus Maachii. Gerst. 
Genus Carinifex. W. G. Binney.f 1863. 
Soft parts resembling Planorhis. Tentacles apparently 
shorter. (Lea.) 
Teeth (See figure II.). 
Shell with angulated whorls and a wide funnel-shaped um- 
bilicus. 
Type Carinifex Newberryi = Planorhis Newherryi. Lea. 
Sub-genus Yorticifex. Meek. 
"VYhorls rounded above. Adult shell smooth or marked by 
lines of growth. Young shell provided with strong transverse 
costse. 
Type Yorticifex Tryoni., = Carinifex Tryoni. Meek. 
Fossi! in thè Tertiaries of ISTevada. 
The above name is proposed by Mr. Meek for thè remark- 
able form above indicated, which was obtained by thè U. S. 
Geol. Survey, of thè lOth parallel, under Clarence King. 
* Mem. St. Petersburg Acad. Sci., ix. p. 527, 1860. See also Eevueet Magas. 
de Zool. 1860, p. 527. PI. 23. The typical species beare no little resemblance 
to Carinifex., and, though smaller, may be congeneric. It has several years’ 
priority. 
f Megasystropha. Lea. Neither genus was characterized by thè author, and 
thè former is in generai use and has priority. 
