250 PROCEEDINGS OF THE ACADEMY OF [Mch., 



The penis has low, slowly spiral ridges. The entire length of the organs 

 exserted is about 3.2 mm. 



The jaw ha*? about 7 unequal ribs. 



The teeth number about 16.12.1.12.16, the tenth to thirteenth being 

 transitional. Both cusps of the marginal teeth are bifid. 



Five shells taken in Sawmill Canyon, running from Bear Park, 

 Chiricahuas, are like the types. The periphery in some is not quite so 

 angular. The punetulation is identical. Two measure: 

 Alt. 7.5 7 mm. 



Diam. 16.3 14 " 



Whorls 6i 6i 



Group of A. chiricahuana. 



Aperture toothless. Epiphallus and duct of the spermathcca very 

 much longer than in species of any of the other groups, the diameter 

 of the shell contained four times in the length of the penis, epiphallus 

 and flagellum. 

 Ashmunella chiricahuana (Dall). PI. XVI, figs. 96-100. 



Polygyra chiricahuana Dall, Proc. U. S. Nat. Mus., XVIII, p. 2, 1895 (Fly 



Park, Chiricahua Mountains); Proc. U. S. Nat. Mus., XIX, p. 341, PI. 32, 



figs. 9, 10, 12, 1896. 

 Ashmunella chiricahuana (Dall), Pils. and Ckll., Proc. Acad. Nat. Sci. Phila., 



1899, p. 192; Ancey, Jour, of Malacol., VIII, September, 1901, p. 76, with 



var. varicifera, p. 77. 



This species has the general shape and rounded periphery of A. 

 levettei. It varies from chestnut to rather light greenish-brown, and 

 shells which have lost their cuticle are dull flesh-colored. It is very 

 glossy and smooth, marked with weak growth-wrinkles and engraved 

 spirals, which are distinct in some, almost obsolete in other specimens. 

 Under the compound microscope fine spiral striae are seen to cover the 

 surface between the spiral lines. Whorls about 5h, slightly convex. 

 The last descends a trifle in front, and is somewhat constricted behind 

 the lip. The aperture is without teeth. The lip is narrow, reflexed, 

 brownish above and at the edge, without trace of lip-teeth. The umbili- 

 cus opens rather widely at the last whorl. 



There is almost always an opaque yellow stripe on the last whorl, 

 marked inside by a strong white rib, and indicating a place of growth- 

 arrest. Some shells have several such variceal streaks on earlier whorls 

 also. The feature is a variable one in shells of the same lot, for reasons 

 I have elsewhere discussed in full. In one lot of 16 specimens from 

 Cave Creek Canyon, Chiricahuas, there are 3 specimens with a single 

 streak on last whorl, 8 with 2 streaks on last 2 whorls, 4 with 3 streaks 

 on last 3 whorls, and 1 with 4 streaks on last 3 whorls. 



