1916.] NATURAL SCIENCES OF PHILADELPHIA. 315 



HUNTING MOLLUSCA IN UTAH AND IDAHO. 

 BY JUNIUS HENDERSON AND L. E. DANIELS. 



The investigations of Hemphill prior to 1890 in Idaho and north- 

 eastern Utah, made that region classic ground in western American 

 conchology. ( >wing to the existence of many small mountain ranges, 

 in most instances conchologically unexplored, isolated by great 

 expanses of arid territory wholly unfavorable to the larger land 

 snails, in western Utah, Idaho, and Nevada, that area is an attractive 

 field, and some of us have viewed it with longing. It is likely that 

 every range not yet explored will yield one form or more of Oreohelix 

 new to science. Indeed, we found a very interesting new form very 

 close to one of Hemphill's localities, and in the same range. Probably 

 Utah is approximately the center of distribution of the genus 

 Oreohelix, and a thorough understanding of its forms and their 

 distribution and habits may throw considerable light upon general 

 problems of distribution of plants and animals in the Rocky Moun- 

 tains and Great Basin, a thing devoutly to be wished. Before 

 beginning serious work upon the unexplored ranges, it seemed to us 

 important to clear up" some of the many difficulties arising from a 

 critical study of Hemphill's records and collections, in order to reach 

 a better understanding of his species and varieties. He explored 

 particularly the western edge of the Wasatch mountains and their 

 spurs bordering the Great Salt Lake Basin on the east, thence north- 

 ward into Idaho and southwestward to the Oquirrh Mountains, 

 which extend southward from the southern end of Salt Lake. His 

 published localities are exceedingly indefinite, as applied to snails 

 of a genus whose colonies are usually of very limited extent and 

 whose varieties are in many instances limited in their known range 

 to the type locality. They were found to be even more indefinite 

 in the field than they looked on paper. In the collections he dis- 

 tributed the labels are still more vague and sometimes misleading. 

 However, we obtained material from somewhere near some of his 

 stations, at least. 



Inconsistencies in the descriptions and figures of material collected 



by Hemphill render the determination of some of the snails of the 



region difficult. We have been greatly assisted in this work by the 



loan to the University of Colorado, by Dr. Geo. H. Clapp, of his two 



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