1912] Taylor: Birds and Reptiles of Northern Nevada. 333 



alders were observed near the Leonard Creek Ranch. A short 

 distance above our camp, which was located at 6500 feet altitude, 

 patches of chinquapin were in evidence, and on certain nearby 

 ridges, at altitudes not much greater than that at which our camp 

 was located, mountain mahogany trees were found. 



It is rather difficult to decide whether the Leonard Creek 

 flats should be regarded as Transition or Upper Sonoran. Ele- 

 ments of both were present. Neotoma cincrea occidentalis was 

 taken in a rocky outcrop at 6500 feet altitude. Perognathus 

 parvus olivaceus was quite common, and Microtus mordax, Odo- 

 coileus hemionus, and Citellus or ego mis were recorded. On the 

 other hand, Beithrodontomys megalotis deserti was fairly abun- 

 dant and cottontails and jackrabbits ranged commonly over the 

 flats. Among bird species noted, Spizella hreweri, Oreoscoptes 

 montanus, and Centrocercus urophasianus were present in 

 greatest numbers. White-crowned sparrows, green-tailed tow- 

 hees, sage sparrows, and vesper sparrows were all noted. One 

 difficulty is apparent in attempting to use species of birds as 

 zone indicators at this time of year (August 1 to 8), namely 

 that many species were no longer nesting and were migrating 

 locally. This probably accounts for the presence at this locality 

 of the white-crowned and sage sparrows, both of which were in 

 all likelihood out of their breeding zone. 



It may be said that in all probability the Leonard Creek flats 

 (altitude 6000 to 7000 feet) should be regarded as an area of 

 overlapping Transition and Upper Sonoran, with the emphasis 

 placed on the Transition. This zone certainly follows the stream 

 down nearly to Leonard Creek Ranch. The assemblage of forms 

 more typically Upper Sonoran at the ranch itself is sufficiently 

 predominant to warrant its reference to that zone. 



THE LIFE ZONES OP THE PINE FOREST MOUNTAIN 



REGION 



(See map, plate 7) 

 The region here considered is doubtless fairly typical of the 

 Great Basin in northern Nevada, so that general conclusions as 

 regards life zones, with due regard for local modifying factors, 

 may be widely applicable to the northern Great Basin region. 



