198 PROCEEDINGS OF THE ACADEMY OF [March. 



Trail, below the cross-bed sandstone, and in "Spectacle Cove," Station 

 A, at about the same level. It was not taken north of the Grand 

 Canyon. 



LYMN^ID^l. 

 Lymnaea parva Lea. 

 Pipe Spring, Ariz. 



Lymnaea obrussa Say. 



Deception Lake near Kanab, Utah, small, slender specimens. 

 Planorbis tenuis Phil. 



Reservoir back of Williams, Ariz. 

 Planorbis deflectus Say. 



Fredonia, Ariz., Station 38, near the Utah boundary. 



PHYSID^. 



Physa virgata Old. 



Reservoir back of Williams; Pipe Springs, Vermilion Cliffs, Station 

 39. Physa traskii Lea and Ph. orbignyana Lea are synonymous with 

 virgata. 



Physa humerosa Gld. 



Indian Gardens on the Bright Angel Trail in the Grand Canyon 

 (C. M. Cooke). A small form, evidently referable to this species. 

 Physa gyrina Say. 



The Greens, near Kanab, Utah. Another small Physa of uncertain 

 identity was taken in Deception Lake, Utah. 



SPTUERUD2E. 

 Pisidinm sp. undet. 



The Greens, Kanab C?eek, near Kanab, Utah. 



Explanation of Plates XII, XIII, XIV. 



Plate XII. — Figs. 1-14. — Oreohelix yavapai profundorum P. and F. Cotypes. 



Spectacle Cove. No. 103,234 Acad. Nat. Sci. Phila. 

 Figs. 15-17. — Oreohelix yavapai extremitatis P. and F. Station C, Upper 



talus, west of Bass Camp. No. 103,237. 

 Figs. 1S-21 — 0. y. extremitatis P. and F. Cotypes. 100-400 feet below the 



rim along the trail near Bass Camp. No. 103,236. 

 Figs. 22-24. — Oreohelix yaimpai angelica P. and F. Cotypes. 100-400 feet 



below the rim. Bright Angel Trail. No. 103,239. 

 Fig. 25. — O. y. angelica. Same locality. No. 103,241. 

 Figs. 26-2S. — Sonorella coloradoensis (Stearns). Whitish, bandless form 



from White Creek, 1 mile above its junction with Shinumo Creek, Grand 



Canyon, north side. No. 103,255. 

 Figs. 29, 30. — Sonorella coloradoensis (Stearns). Head of Starvation Tank 



Wash, Grand Canyon, south side. 



