[ 67 ] 



* 

 * * 



Mexican Sjtecies. 

 5. Arionta E^mondi, Try on. 



Plate 5, fig. 18. 



Turbinately globose, very thin ; whorls 4, scarcely striate, 

 (punctate when viewed with a lens,) slightly convex, the last 

 large, rounded; base convex; umbilicus narrow, with an an- 

 gled margin ; aperture obliquely semilunar, lip expanded. 

 Light corneous, with a narrow brown band on the periphery, 

 and above the suture on the spire. 



Diam. 17, height 12 mill. 



Cinaloa, near Mazatlan. 



6. Arionta Humboldtiana, Valenciennes. 

 Plate 6, figure 17. 



Ventricose, roughly irregularly striate and wrinkled, malle- 

 ated ; spire small, acuminate ; whorls 4, rapidly enlarging, the 

 last very large ; aperture oblique, large, lip expanded, its ex- 

 tremities connected by a thin testaceous deposit; umbilicus 

 partly covered. Grayish-white, with three rufous bands on 

 and above the periphery. 



Diam. 37, height 28 mill. 



Mexico. 



I include this species because it was figured by Dr. Binney 

 in his Terrestrial Mollusks, by error, as Pomatia aspersa. It 

 does not even belong to the same genus, although placed there 

 by Albers. 



POLYMITA, Beck. 



This group includes, according to Albers, a large collection 

 of West Indian species, to which we now add several Califor- 

 nian forma. 



