282 PROCEEDINGS OF THE ACADEMY OF [Mch., 



ined ; it differs from 0. y. neomexicana chiefly by the stronger spiral 

 sculpture of tho embryonic shell and the abrupt change in sculpture at 

 the inception of the neanic growth. The same differences and the wider 

 umbilicus separate it from the northern 0. hemphilli, which, moreover, 

 differs by its dentition, as indicated below under 0. y. neomexicana. 



The penis (PI. XIX, fig. 7) resembles that of 0. y. neomexicana 

 except that it is larger, and the vas deferens enters the epiphallus 

 centrally at the apex. There were 10 embryos in the uterus, each 

 half enveloped in its podocyst. 



The jaw has longitudinal and vertical striae. The radula (PI. XXII, 

 figs. 7) has 26.1.26 teeth, those in the middle unicuspid; the ectocone 

 distinctly appearing on the sixth. Marginal teeth bicuspid, the cusps 

 unsplit. 



Oreohelix yavapai neomexicana d. subsp. P!. XI. figs. 8. 9 ; PI. XXV, fig. 59. 



The shell is thin, brown, acuteh^ keeled, pinched in above and below 

 the peripheral keel, which extends to the aperture, the whorls else- 

 where convex above and below. Embryo of 2 to 2^ whorls, convex 

 except near the periphery where they are impressed ; they are densely 

 striate obliquely and rather obsoletely striate spirally. The junction 

 with the subsequent neanic growth is often indistinct. Whorls 4f to 

 5^, the later ones rudely, very obliquely wrinkled, and showing raised 

 spiral stride, usually rather indistinct. The umbilicus is ample within 

 and rather widely open, exposing the penultimate whorl. Aperture 

 small with simple lip, the whorl descending slowly to it. 



Alt. 8.5 7.8 mm. 



Diam. 15.6 14.5 '' 



Canyon Diablo, near Rowe, San Miguel county. New Mexico. Types 

 No. 84,297, A. N. S. P., collected by Miss Mary Cooper. 



This form differs from 0. hemphilli (Newc.) by its less convex em- 

 bryonic whorls, w^hich are more impressed near the periphery, and by 

 the more ample umbilicus ; but it differs chiefly by the unicuspid teeth 

 of the median part of the radula, those teeth in 0. hemphilli having well- 

 developed ectocones, as in 0. harhata. It seems to be rather widely 

 separated geographically from the range of 0. hemphilli. 



It is also before me from Beulah, in the Sapello Canyon, San Miguel 

 county, at 8,000 feet (Prof. Cockerell), small specimens only 10 mm. 

 diameter, with 4^ whorls, perhaps not quite adult. Similar small speci- 

 mens come from Las Huartes Canyon, Bernalillo county. New Mexico 

 (Miss Cooper). 



