1915.] NATURAL SCIENCES OF PHILADELPHIA. 385 



Zonitoides minuscula alachuana (Dall). 



Dragoon Mountains: Stations 1, 6|, 10, 15, 26, 28, 29. 

 Striatura milium meridionalis P. and F. 



Dragoon Mountains: Stations 1, 6, 10, 29. 

 Euconulus fulvus (Miill). 



Dragoon Mountains: Stations 1, 10, 15, 28 and E. f. alaskensis. 

 Station 29. 



ENDODONTIDuE. 

 Pyramidula cronkhitei (Newc). 



Dragoon Mountains: Stations 28, 29. 

 Radiodiscus millecostatus Pils. and Ferr. 



Dragoon Mountains: Stations 1 and 10; rare. 



Helicodiscus arizonensis Pils. and Ferr. 



Dragoon Mountains: Stations 1, 6^, 10, 28, 29. 



Punctum califomicum Pils. 



Dragoon Mountains: Station 10, in the amphitheatre or upper 

 basin of Tweed Canyon. The specimens are a little more openly 

 umbilicate than the type, but the riblets are more unequal than in 

 P. pygmceum, and spiral lines are scarcely discernible. 



SUCCINEID^. 

 Succinea avara Say. 



Dragoon ^Mountains: Stations 2, 3; single dead specimens. 



FERUSSAOID^. 

 Cochlicopa lubrica (Moll.). 



Dragoon Mountains: Stations 1, 6, 6^, 10, 15, 28, 29. Abundant. 



PUPILLID^. 

 Bifidaria ashmuni Sterki. 



Dragoon Mountains: Stations 1, 3, 6, 10, 11, 15, 25, 26, 29. 

 Bifidaria perversa Sterki. 



Dragoon Alountains: Stations 2, 3, 22. 

 Bifidaria dalliana Sterki. 



Dragoon Mountains: Stations 3, 6, 26. 



Bifidaria pilsbryana Sterki. 



Dragoon Mountains: Stations 1, 2, 10, 11, 15, 18, 25, 28, 29. 

 Vertigo coloradensis arizonensis P. and V. 

 Dragoon Alountains: Station 25. 



