350 



PROCEEDINGS OF THE ACADEMY OF 



[May, 



The central and inner lateral teeth have no side cusps. There 

 are about 12 lateral teeth on each side (Station 30). In an individual 

 from Station 36 there are 17, 13, 1, 13, 17 teeth. The transition from 

 lateral to marginal teeth is very gradual in this species, so that the 

 exact number of laterals is somewhat uncertain. 



Oreohelix rugosa (Hemphill). PL 22, figs. 7, 7a. 



The penis is about two-thirds the diameter of the shell, therefore 

 shorter than in any form of 0. s. depressa examined. Its internally 

 costate lower portion is relatively decidedly longer than in 0. s. 

 depressa, being over half the total length, agreeing with that of 

 0. cooperi. Inside the lower part has 5 or 6 fleshy ribs, smooth, as 

 usual, and the upper part has about the same number, but they are 

 lower, and both ribs and intervals are papillose. The duct of the 

 spermatheca is longer than in 0. s. depressa. Two individuals 

 measure : 



There are about 13 lateral teeth on each side, the inner 9 to 11 

 without side cusps. The transition to marginals is very gradual. 



Oreohelix cooperi (W. G. B.). PI. 22, figs. 1, 2, 3, 4. 



Specimens from Wyoming, Utah, Colorado and New Mexico 

 have been dissected. All agree in having the internally costate 

 part of the penis longer than the papillose part, which at once differ- 

 entiates the species from 0. strigosa and 0. peripherica, in which the 

 costate part is much shorter than the papillose part. The penial 

 retractor is short, less than half the length of the penis in the smaller 

 specimens, but about two-thirds the length of penis in the large 

 forms from Yellowstone Park and New Mexico. The median part 

 of the penis is often somewhat swollen, but in other examples this is 

 not noticeable. 



The penis has usually four main fleshy ridges in the lower part 

 as in specimens from McCammon, Idaho (fig. 2), and the Black Range 

 of New Mexico, or there may be about 6 unequal ridges (fig. 1, 

 Yellowstone Park, No. 96,973), one of them continuing upwards 



