452 U. S. NATIONAL MUSEUM BULLETIN 2 1 1 



arity under these circumstances is surprising. Perpetually wandering about the 

 feet of the draught animals, or perching upon their backs, they become so accus- 

 tomed to man's presence that they will hardly get out of the way. I have even 

 known a young bird to suffer itself to be taken in hand, and it is no uncommon 

 thing to have the birds fluttering within a few feet of one's head. The animals 

 appear to rather like the birds, and suffer them to perch in a row upon their back- 

 bones, doubtless finding the scratching of their feet a comfortable sensation, to 

 say nothing of the riddance from insect parasites. 



A singular point in the history of this species is its unexplained disappearance, 

 generally in July, from many or most localities in which it breeds. Where it goes, 

 and for what purpose, are unknown; but the fact is attested by numerous ob- 

 servers. Sometimes it reappears in September in the same places, sometimes 

 not. Thus, in Northern Dakota, I saw none after early in August. 



This disappearance, which occurs also with the eastern cowbird is 

 evidently for concealment during the molting season. Seton (1891) 

 states: "I noticed that on the Big Plain the cowbirds disappear for 

 a time, apparently joining the rusty grackles and other species among 

 the swamps and wet lands until after the attainment of the fall 

 plumage, when for a time they again become conspicuous, and con- 

 tinue about the pastures until October." 



DISTRIBUTION 



Range. — Western Canada and western United States (except the 

 southwestern portion) east to southern Louisiana south to Mexico. 



Breeding range. — The Nevada brown-headed cowbird breeds 

 from central and northeastern British Columbia (Nulki Lake, Swan 

 Lake, Peace River District), central-southern Mackenzie (Fort Simp- 

 son, Fort Resolution), northeastern Alberta (Athabaska Delta), 

 central Saskatchewan (Flotten Lake, Emma Lake), southern Manitoba 

 (Lake St. Martin, Hillside Beach), and western Ontario (Rainy River; 

 intergrades) ; south through central and eastern Washington (rarely 

 west to Tacoma) and eastern Oregon (Klamath County) to northeastern 

 and central-eastern California (Alturas, Independence), southern Ne- 

 vada (except Colorado River jValley), Utah (except extreme south- 

 western section), northeastern and central-eastern Arizona (Kayenta, 

 Springerville), western New Mexico, Colorado (Fort Lyon), western 

 Nebraska, and through western Minnesota to northwestern Iowa 

 (Sioux City). 



Winter range. — Winters from western and southern California, 

 southeastern Arizona (Tucson), northeastern Texas (Dallas), and 

 southeastern Louisiana (New Orleans, Pearl River) ; south to southern 

 Baja California (Miraflores), Michoacdn (Morelia), Guerrero (Chil- 

 pancingo), and Veracruz (C6rdoba). Rarely east to eastern Iowa 

 (Linn County, Johnston County), and eastern Kansas (Lawrence, 

 Neosho Falls). 



