68 TRYONIA. 



2. TRYONIA PROTEA, Qould. 

 Plate 17, fig. 21. 



Shell elongate, slender, whorls seven to 

 eight, moderately convex with well impressed 

 sutures, cancellated by longitudinal and re- 

 volving ridges ; aperture small, ovate. 



Alt. 7*5, diam. 2*5 mill. 



Colorado Desert, Southern California. 



Differs from No. 1 by its cancellate surface, 

 destitute of ribs. 



Mr. Conrad described this same species un- 

 der the name of Melania exigua, and the date 

 of the publication is given as one month earlier 

 than that of Dr. Gould, but I agree with Mr. 

 Binney, that there is scarcely a doubt but that 

 the latter date is a false one, and Dr. Gould's 

 name was the one really first published. 



(49) 



