1916.] NATURAL SCIENCES OF PHILADELPHIA. 339 



Pisidium huachucanum Pits, and Ferr. 



In a spring near Port Neuf River, north of McCammon, Idaho. 

 Identified by Dr. Sterki. 



Explanation of Plates XV, XVI, XVII, XVIII. 



Plate XV. — Fig. 1. — Oreohelix peripherica, -ix examples from Sta. 26, North 



Ogden Canyon, Utah. 

 Fig. 2. — Oreohelix peripherica, six examples from Sta. o(), near Cache Junc- 

 tion. Utah. 

 Fig. 3.— Oreohelix peripherica, nine examples from Sta. 31. near Cache 



Junction, Utah. 

 Fig. 4. — Oreohelix peripherica, two abnormal specimens from Sta. 4, near 



Trenton, Utah. 

 Fig. 5. — Oreohelix tenuistriata n. sp., 3 views of type specimen from near 



Hot Lava Springs, Idaho. In collection of L. E. Daniels. 

 Fig. 6. — Oreohelix tenuistriata n. sp., 3 views of cotype from near Hot Lava 



Springs, Idaho. In Univ. Colo. Museum. 

 Fig. 7. — Oreohelix hemphilli eurekensis n. subsp., 3 views of type specimen 



from Eureka, Utah, in Univ. Colo. Museum. 

 Fig. 8. — Oreohelix hemphilli eurekensis n. subsp., 3 views of co-type from 



Eureka, Utah. In Acad. Nat. Sci. Phila. 



Plate XVI. — Fig. 1. — Oreohelix strigosa fragilis, six examples from Sta. 39, 



east of Webster, Utah. 

 Fig. 2. — Oreohelix strigosa buttoni, four examples from Sta. 16, Taylor 



Canyon, near Ogden. Utah. 

 Fig. 3. — Oreohelix haydeni gabbiana, five examples from Sta. 15, Oquirrh 



Mts., Utah. 

 Fig. 4. — Oreohelix haydeni hybrida, five examples from Sta. 42, near Logan, 



Utah. 



Plate XVII. — Fig. 1. — Oreohelix haydeni corrugata n. subsp. Three views of 

 four specimens from type lot, Sta. 40, southeast of Webster, Utah. 

 Fig. 2. — Oreohelix peripherica Ancey. Three views of four specimens from 

 Sta. 29, near Cache June, Utah. 



Plate XVIII. — Fig. 1. — Oreohelix haydeni betheli, six examples from type 

 locality, north of river. Glenwood Springs, Colo. 

 Fig. 2. — Oreohelix haydeni betheli var. alia, eight examples from type locality, 



south of river, Glenwood Springs, Colo. 

 Fig. 3. — Oreohelix haydi ni, Gabb's original figure from Amer. Journ. Conch. 



