The Birds of El Paso County, Colorado 459 



Park Cliff Mouse, Peromyscns nasutus, and Gale's Wood Rat, 

 Neoto/ua in. fallax, are quite characteristic of it. Other species 

 range into it from the zones above and below. 



The following birds are quite characteristic of this zone 

 in the breeding season : 



Sharp-shinned Hawk, White-throated Swift, W'right's 

 Flycatcher, Long-crested Jay, Mountain Towhee, Green-tailed 

 lowhee. Plumbeous Vireo, MacGillivray's Warbler, Rocky 

 Mountain Nuthatch, Pgymy Nuthatch, Chestnut-backed Blue- 

 bird. 



The following trees and shrubs are characteristic of this 

 zone : 



Yellow Pine, P. scopulorum, Red or Douglas's Fir, 

 Pseudotsuga mucronata, Willow, S. irrorata, Rocky Mountain 

 Birch, Betula fonfinalis, Alder, Alnus tenuifolia. Beaked Ha- 

 zel-nut, Corylus rostrata, one species of Gooseberry, Ribei 

 ieptanthum, two species of Ninebark, Physocarpus intermedius 

 and P. monygnus, Meadow Sweet, Holodiscus dmnosa and H. 

 uustralis, and Rocky Mountain Maple, Acer glabrum. 



CANADIAN ZONE. 



The Canadian and the two following zones are strictly 

 mountain regions, this one covering the ground from the 

 upper limits of the Transition to between 10,000 and 11,000 

 feet, and is the most extensive in area of the three Boreal 

 zones. It may be characterized as normally a well forested 

 zone, though none of the trees are exclusively confined to it. 



In El Paso County no species of mammal appears to be 

 confined to the Canadian Zone, though there are a number 

 common to it and the Hudsonian, to say nothing of others 

 which are also found in the Transition. The following mam- 

 mals are characteristic of the two lower Boreal zones : 



Fremont's Squirrel, S. fremonti, Woodchuck, Marmota 

 sp., Colorado or Rocky Mountain Red-backed Mouse, Evo- 

 tomys g. galei, Colorado or Mountain Pocket Gopher, Thomo- 



