1912] Taylor: Birds and Reptiles of Xorthern Xevada. 327 



Vireosylva gilva swainsoni. So, keeping in mind the fact that 

 temperature may not be the only or even the principal limiting 

 factor in certain individual cases (of the species cited), still the 

 conclusion is justifiable, that Big Creek Kanch belongs to higher 

 Upper Sonoran than Quinn River Crossing, and may properly be 

 included in the area of admixture of Transition and Sonoran 

 forms, as shown in the accompanying map. 



The Big Creek Camps (4500-8000 feet; Biological Cross-sec- 

 tion Camps nos. 2 to 4; see pi. 8, fig. 2). — From its mouth to a 

 point about a mile into the mountains Big Creek Canon is narrow 

 and fairly steep-sided. Then it begins to widen, until at the 

 forks, about two miles distant from the mouth, a broad series of 

 rolling flats comes to view. If the creek is followed still farther, 

 the caiion once more becomes constricted. 



In the biographic accounts of certain species reference has 

 been made to the ' ' Dugout Camp, ' ' which marks a mining claim. 

 This is located at 5000 feet altitude on Big Creek about half- 

 way between the mouth of the canon and the forks. 



The range in the region of the Dugout Camp and for some 

 distance east and west is made up of steep-sided foothills re- 

 sembling badlands. This series of hills continues for nearly the 

 entire north and south extent of the Pine Forest Mountains. 

 Then at the forks the rolling flats come into view. These are 

 continuous on the south with the even more extensive Leonard 

 Creek flats. From two to four miles farther west the main ridge 

 of the mountains, culminating in DufEer Peak (9400 feet), is 

 seen. 



Biological Cross-section Camp no. 2 (6000 feet; see pi. 8, 

 fig. 2). — This camp was situated on Big Creek about a half-mile 

 above the forks. Artemisia tridentata was the prevailing plant 

 all over the flats and ridges. The trees along the stream, named 

 in the order of their abundance, were quaking aspens, willows, 

 and alders. The flowering plant most in evidence in the open 

 was Lupinus laxiflorus. This camp may perhaps more properly 

 be said to represent lower Transition than high Upper Sonoran. 

 The green-tailed towhee was common, and Citellus oregonus was 

 secured on nearby ridges. The presence of Cliondestes gram- 



