1905.] NATURAL SCIENCES OF PHILADELPHIA, 261 



The radula is like that of Purtyman's ranch hachiiana in general 

 features. The twelfth lateral shows a small ectocono, larger on suc- 

 ceeding teeth. 



Sonorella rowelli (Newcomb). PL XVIII, figs. 33-35. 



Helix rowelli Newc, Proc. Cal. Acad. Sci., Ill, p. 181 (January, 1865). 

 S. rowelli (Newc), Pilsbry, Proc. Acad. Nat. Sci. Phila., 1902, p. .511. 



Shell like S. hachitana, but small, with large mouth and small umbili- 

 cus. Corneous-brown, with a dark band above the periphery, indis- 

 tinct pale borders above and below it; somewhat translucent, thin. 

 Whorls nearly 4^, convex, the first (embryonic) 1^ whorls nearly 

 smooth, sculptured with some slight radial wrinkles only; following 

 whorl or whorl and a half showing some indistinct granulation in places; 

 last whorl with growth-lines only, rounded peripherally, descending a 

 little in front. The aperture is large, subcircular, oblique, the thin 

 whitish peristome being very narrowly expanded, columellar margin 

 dilated. Umbilicus comparatively narrow^ partially covered by the 

 columellar lip. 



mm. 



Sanfords, near the eastern border of Pima county, southeastern Ari- 

 zona. No. 83,273, A. N. S. P., collected by James H. Ferriss, 1902 

 (figs. 33, 34). 



Genitalia (PI. XX, figs. 13, 14). The penis is .short, containing a 

 short, cylindric, obtuse papilla. The free portion of the epiphallas is 

 about equal to the penis in length. The flagellum is reduced to a mere 

 tubercle, being much shorter than in any other Sonorella yet dissected. 

 The vagina is about as long as the penis, and the spermatheca and its 

 duct are about four times as long. 



The jaw has 6 or 7 narrow, unevenly spaced ribs. 



The radula has 44.1.44 teeth, like those of *S'. granulatissima. The 

 eleventh and twelfth are transitional. 



The last whorl is less deflexed than in S. h. howiensis, the aperture 

 is larger and the umbilicus smaller. Both penis and vagina are de- 

 cidedly shorter, though their proportionate lengths do not differ ma- 

 terially, and both have the penis-papilla short and obtuse; but in 

 S. rowelli the flagellum is reduced to a minute vestige, unlike any of the 

 other species. The remarkable constancy of this organ in the large 

 number of individuals of Sonorella and Ashmunella which have been 



