400 PROCEEDINGS OF THE ACADEMY OF [Juiie, 



PUPOIDES MARGINATA (Say). 

 BiFIDARIA PROCERA CRISTATA P. and V. 



"■ PELLUCIDA HORDEACELLA (Pils.). 



" TUBA P. and F. 

 Vertigo ovata Say. 

 Lymn^^a parva Lea. 



" OBRussA Say. 



" BULIMOIDES COCKERELLI P. and F. 



PlANORBIS TENUIS Phil. 



" CARIBOUS Orb. 



" PARVUS Say. 



" ARizoNENSis P. and F. 



Physa virgata Gld. 

 Paludestrina protea (Gld.). 

 PisiDiUM PAUPERCULUM (Sterld).^ 



" COMPRESSUM Prime (kirklandi Sterki). 

 Anodonta dejecta Lewis, fossil and recent, fragmentary. 



In the drift debris of the Santa Cruz River at Amado's Ranch 

 (not far from the mouth of Sopori Creek) we took the following: 



Zonitoides singleyana (Pils.). 

 " minuscula (Binn.). 



Pupoides MARGINATA (Say). 



BiFIDARIA PELLUCIDA HORDEACELLA (Pils.). 



" PERVERSA Sterki. 



" PROCERA CRISTATA P. and V. (one specimen). 



" PENTODON (Say). 



Vertigo ovata Say. 

 Vallonia perspectiva Say. 

 Physa humerosa Gld. 



" VIRGATA Gld. 



On Sopori Creek, five miles west of Amado's Ranch. 



Thysanophora hornii (Gabb). 

 Pupoides marginata (Say). 

 Physa sp. undet. 



Sonorella arizonensis (Dall). 



Epiphragmophora arizone'nsis Dall, Proc. U. S. Nat. Mus., XVIII, p. 1, 189.5. 

 Sonorella arizonensis (Dall), Bartsch, Smiths. Misc. Coll., XLVII, p. 198, 

 PL 33, fig. 6. 



This is a rather globose species with narrow umbilicus, quite 

 unlike anything we found. The type is a bleached specimen found 

 in the Santa Cruz River at Tucson, which no doubt drifted down 

 from above. As no Sonorella lives at or near the river level, it must 

 have been washed down from some . mountain or rocky hill in the 



^ The species of Pisidium in these lists were determined by Mr. E. G. Vanatta. 



