134 
BIRDS : GENERAL CONSIDERATIONS. 
and moderate elevation, might reasonably be expected to occur. 
Though some of these deficiencies are doubtless, in part, due to 
causes other than those acting directly on the physical organization, 
they furnish the investigator entering the region the first insight into 
its true faunal character. 
Passing along the Big Indian Valley, among the songs of the com- 
mon birds along the way there were missed the notes of such famil- 
iar species as : the Brown Thrush, the Warbling, Yellow-throated, 
and White-eyed Vireos, the Chewink, the Meadow Lark, the Great- 
crested Flycatcher, and the Orioles and Cuckoos. Some of these 
species were sparingly represented in the main valley, but none ap- 
peared to regularly extend into the secondary valleys at this portion 
of the region. Other familiar species, of which mention is made 
beyond, although somewhat generally distributed were not abundant 
and were rather restricted in their local distribution. Of the familiar 
birds, one only, the Cliff Swallow, seemed to be more abundant 
than in the region with which I have compared this. This bird, from 
its numbers and domestic habits, was conspicuous and well-known 
all along the valley, and far outnumbered the Barn Swallow, the only 
other species which occurred. 
Another feature to be noticed in this hasty comparison was a local 
variation in the habits of some of the birds between this and other, 
more settled, districts. Certain species which, closer to civilization, are 
more or less familiar and confiding in disposition, often making their 
abode in the close vicinity of man, here were rarely found about hu- 
man habitation, although well represented in the wilder portions of 
the valleys or even in the mountains. This was very noticeable in the 
cases of the Wood Thrush, Scarlet Tanager, and Golden-crowned 
Thrush; and less so with the House Wren, Purple Finch, Least Fly- 
catcher, and other species. In the case of the Wood Thrush these 
habits seemed to be quite general throughout, but with most of the 
other species appeared to be more or less local, seeming to be di- 
rectly dependent on the extent of settlement. Thus about the vil- 
