272 ZOOLOGY BIRDS. 



amount of brown; third marked with white along the inner margin of inner web. Bill 

 black above, bright yellow below. Iris bright yellow. 



Fall specimens have the chestnut of the back much darker; the ashy brown on 

 the flanks much more conspicuous. In young birds, the iris is light yellow, or, more 

 rarely, hazel. 



The Mexican Snowbird, hitherto known only from the table lands of 

 Mexico, was found by our party to inhabit, in great abundance, the mount- 

 ains of Southern Arizona, where they were found breeding in August at 

 an altitude of about 9,500 feet. They inhabited all sorts of localities, being 

 found in the deep pine woods, in the more open aspen groves on the mount- 

 ain sides, and along the little alpine streams that made their way down hero 

 and there from hidden springs in the mountains, and were often entirely 

 shut in by the growth of alders and other deciduous shrubs. A lumberman's 

 camp, which had been established here a few months before, proved to be 

 a favorite point of rendezvous ; and thither they nocked in the early morn- 

 ing, in merry sociable companies, to glean the oats scattered about by the 

 horses during the morning meal, and the crumbs thrown out from the log- 

 shanties. In a very short space of time, they had familiarized themselves 

 to the presence of man, and, instead of shunning his neighborhood, had 

 evidently taught themselves to look upon him rather in the light of a bene- 

 factor than an enemy. A single nest was found here August 1, which con- 

 tained four fresh eggs. This doubtless was a second hatching, as great 

 numbers of the young were about, and a few just beginning to assume the 

 adult livery. 



The nest was placed beneath a small overhanging rock in a deep 

 grove of pines. It was quite similar in construction to the one just noted ; 

 but the grasses and fibrous materials were more firmly woven and more 

 warmly lined with fine grass. The eggs have the same greenish-white 

 ground color, which in two is almost immaculate ; but careful examination 

 shows the presence of a few minute punctate reddish-brown spots, irregu- 

 larly disposed over the surface, while, in the third and fourth, these, though 

 still minute, are more pronounced. 



The interval existing between the two forms of caniceps and cinereus, 

 as shown by a large suite of the former, collected by the expedition in Southern 

 Colorado in 1873, and an equally large number of the latter, gathered in 



