12 LAND AND FllXbll-AVATER SHELLS OF N. A. [PART IIL 



the original specimens collected by Dr. Le Conte. Mr. Conrad's 

 description, given below, bears an earlier date than that of 

 Dr. Gould, but was not actually published at that tirue. I have, 

 therefore, retained Dr. Gould's name. The two descriptions 

 evidently refer to the same species. 



Melania exiijua. — Turreted ; volutions 8, disposed to be angulated and 

 somewliat scalariform above, cancellated, longitudinal lines 

 pj 141, wanting on tbe lower ,lialf of the body whirl ; columella re- 

 flected ; aperture elliptical. Length one-fifth of an 



inch. Colorado Desert, California. (Dr. Le Conte.) tt i tn 

 ' ^ ' Fig. 142. 



The specimens are numerous and of a chalky 



whiteness, showing tha.t they are all dead shells. ^ 



Said to have been found one hundred and twenty ^S 



miles distant from any stream passed on the route. ^P 



ea-ifua '^™ indebted to Dr. Caspar Parkinson and Mr. Tryonia 



enlarged. Mactier for specimens. (Conrad.) protea. 



Fig. 142 is drawn from one of Dr. Gould's original specimens. 



Cat. No. Xo.of Sp. 



9143 4 



93.56 4 



Locality. j From ■whom received. I Remarks. 



Colorado Des. 



Prof. Haldeman. M. exigua, teste Conr. 

 Mr. Mactier. " " 



COCHLIOPA, Stimpsox. 



Lingual dentition of the typical species : Rhachidian tooth 

 short and broad ; middle lobe of the basal margin very broad ; 

 basal teeth rather large. Intermediate tooth with a long pe- 

 duncle, and square body having a cavity in tbe centre. Lateral 

 teeth with an expansion of the inner side of the shank, separated 

 from the summit by a deep rounded sinus ; the outer lateral 

 being more expanded than the inner. Formula of the denticles : 

 ^2 - 8 - 18 - 24. Shell depressed-conic ; base concave, carinated ; 

 umbilicus large and deep ; aperture oblique. Operculum thin, 

 corneous, sub-spiral. Rostrum of moderate size ; tentacles rather 

 long, ta})ering. Verge rather elongated, compressed, geniculutcd, 

 and bifid, the inner branch being ve.-y small, less than one-fourth 

 ' the size of the outer one and arising at the inner angle of the 

 geniculatiou. 



