330 University of California Publications in Zoology. [Vol. 7 



finches, Audubon warblers, Clarke nutcrackers, white-crowned 

 sparrows, and western red-tails were numbered. The following 

 mammals were noted: Odocoileus hemionus, CallospermopMlus 

 trepidus, Eutamias pictus, Peromyscus maniculatus sonoriensis, 

 Microtus mordax, Zapus princeps oregonus, Canis lestes, and 

 Myotis lucifugus longicrus. The latter was a species of mammal 

 noted at the Duffer Peak meadow only. 



The limber pines and the presence of a number of species 

 usually ranging into zones above Transition gave to the locality 

 a distinctly Boreal coinplexion. As in the case of the head of 

 Big Creek, the predominant Transition facies was somewhat 

 diluted by the addition of certain Boreal elements. It seems 

 appropriate, therefore, to regard the locality as Transition with 

 a marked Boreal infusion. 



Alder Creek Camps (5000-7000 feet; Biological Cross-section 

 Camps nos. 6 to 8). — The mountains grade off to the west more 

 gradually, locally at least, than they do to the east. As is the 

 case with certain other desert ranges, as well as with the Warner, 

 Sierra Nevada and other mountains of California, there is a 

 line of faulting along the eastern side, which accounts for the 

 greater steepness upon that slope. 



The western slopes seem more rocky and are apparently made 

 of harder material, as the canon-sides are steeper. There are 

 great masses of igneous rock. In the vicinity of Alder Creek 

 Ranch especially, much scattered pumice stone was noted. 



"While in general the flora as regards species was the same as 

 on the eastern side, it was noticeably more sparse, and the ridges 

 and flats of the western slope had even more of an arid and 

 baked appearance than those of the eastern. 



Biological Cross-section Camp no. 6 (7000 feet). — In favor- 

 able situations along the stream, for the most part above this 

 altitude, quaking aspens formed rather dense groves. As a rule, 

 north-facing slopes, i.e., on the south side of the canon, were 

 covered with a scattering, sometimes with a dense, growth of ' 

 these trees. Clumps of willows occurred along the stream, and 

 on the arid, exposed ridges mountain mahoganies were fairly 

 common. 



The vicinity of Camp no. 6 must apparently be referred to 



