1917.] NATURAL SCIENCES OF PHILADELPHIA. 59 



Sta. 8^', three miles up St. Charles Canyon, west of St. Charles, 

 Idaho. Oreohelix strigosa depressa (Ckll.) found sparmgly in sand- 

 stone slides and about limestone ledges. In the water-cress of a 

 small seepage channel from the creek we found: 



Paludestrina longinqua (Gld.). Lymncea obrussa Say. 



PJujsa ampuUacea Gld. Succinea rusticana Gld. 



Sta. 82, mouth of Garden City Canyon, west of Garden City, 

 Utah, on south side of canyon. Oreohelix haydeni hyhrida (Hemph.). 

 typical, as at Logan, common under small shrubs, and especially 

 under the matted radical leaves of Balsamorrhiza sagittata (Nutt.), 

 on limestone slopes devoid of rock slides. We also found a few 

 Pwpilla hlandi (Morse). The slopes are now very barren, but we 

 were informed by pioneers that forty-five j^ears ago they were well 

 covered with large mountain mahogany, up to a foot in diameter, 

 as at Sta. H, in the IMcCammon district. These trees furnished 

 fuel for the early settlers, but wasteful cutting and fires have denuded 

 the hills for some miles back, and overgrazing ))y stock has been 

 disastrous to the smaller shrubs and herbs. It is difficult to believe 

 that snails could obtain a foothold under present conditions, but 

 having flourished here under more favorable conditions, they have 

 been able thus far to survive the change in environment. Erosion 

 is rapidly carrying the soil and vegetative debris from beneath the 

 scant shrubbery and may soon destroy the colony, unless saved hj a 

 series of years of increased moisture favorable to plant growth. 



Sta. 83, south side of next canyon south of Sta. 82 and about half 

 a mile distant. Oreohelix cooperi (W. G. B.) abundant, but much 

 smaller than at most localities where we have found this species 

 (diameter 14 mm. to 15.5 mm.). These specimens agree with those 

 from Eureka, Utah, in their small size and the absence of the color 

 bands from below, many of them having no color bands at all. 



Sta. 84, stagnant pool bj^ the roadside, two miles south of Garden 

 City, Utah. Lymncea obrussa Say abundant, L. humilis modicella 

 Say rare. 



Sta. 85, along wagon road from Garden City to Logan, a mile east 

 of the "Sink Holes," east of the crest of the divide. We picked up 

 one large bleached shell of Oreohelix cooperi (W. G. B.), but, as we 

 had a hard day's trip ahead, we did not stop to search for more. 



Preston, Idaho. 

 Sta. 97, bank of Bear River, south and southeast of the wagon 

 bridge due west of Preston. A layer of sand in the bank, several feet 

 in thickness, yielded the following fossils: 



