244 PROCEEDINGS OF THE ACADEMY OF [Mch., 



This species differs from A. angulata by its contiguous basal teeth, 

 but' is related to it by the punctate surface. It resembles A. dupHci- 

 dens in some respects, but the basal teeth are not nearly so closely 

 united "as in that snail, the periphery is carinate, not merely angular, 

 and the whole shell is much more depressed. 



Ashmunella duplicidens n. sp. Pi. XVI, figs. 103-107. 



Shell depressed, vmabilicate, brown or corneous-brown, glossy and 

 sculptured with minute growth-lines only. The spire and base are 

 convex, the periphery obtusely subangular in front, and situated above 

 the middle of the last whorl. There are 5f to 6^ closely coiled, narrow 

 and moderately convex whorls, the last one very slightly descending 

 in front. The aperture is ear-shaped, very oblique, the lip white, well 

 re flexed, and convex on the face. Within the outer margin there is a 

 somewhat retracted broad tooth, prominent at its two ends, concave 

 between them. Upon the basal lip there is a less widened, more emerg- 

 ing double tooth, the outer cusp larger than the inner. The parietal 

 wall bears an oblique, straight lamella. 



Alt. 6.5, diam. 13 mm. 

 " 5.9, " 12 " 



Bearfoot or " Bar " Park, Chiricahua Mountains, Arizona, at an 

 elevation of 8,500 feet. 



This species is an important link in the A, levettei chain, showing the 

 origin of the two basal teeth by splitting of an original median one. It 

 is less differentiated from the group of A . thomsoniana than the other 

 known Arizona species. 



The genitaha (PI. XXI, fig., 23) also resemble those of thomsoniana. 

 The general proportions are shown in the figure and table of measure- 

 ments. The penis is comparatively long. The duct of the sperma- 

 theca is large, weakly varicose, and contracted where it joins the 

 vagina. I did not make out any lower attachment of the penis 

 retractor muscle. 



There are about 18.10.1.10.18 teeth, nine or ten being laterals, the 

 next three or four transitional. The ectocone is not split on the mar- 

 ginals, at least not on most of them. 

 Ashmunella angulata n. sp. PI. XI, fig. 11 ; PI. XIV, figs. 55-61, 63, 64. 



The shell is lens-shaped, angular peripherally, rather narrowly um- 

 bilicate, glossy, reddish-chestnut when unworn, paler and more cor- 

 neous around the umbilicus and in the middle portion of the upper 

 surface, but frequently dull throughout by slight wear of the surface. 

 Sculpture of very fine and irregular gro\\i:h-lines, and for a short space 



