BIRDS OF COLORADO. II3 



636. Mniotilta varia. Black and White Warbler. 



Summer visitant; rare. An eastern species scarcely com- 

 ing west of central Kansas. Has been taken twice, once by 

 Minot at Boulder, June i, 1880 (B. C. N. O. V. 1880, 223), and 

 Geo. F.!Breninger writes that he took one at Table Rock, on 

 the Divide between Denver and Colorado Springs. Not known 

 to breed in Colorado, though breeding in corresponding lati- 

 tudes in Kansas. 



644. Helminthophila virginiae. Virginia's Warbler. 



Summer resident; common. Most common at the limit of 

 its eastern extension at the base of the foothills and though so 

 common there it is not known a few miles out on the plains at 

 Pueblo. This is one of the few exceptions to the rule that any 

 western species found in the foothills follows down the Arkan- 

 sas at least as far as Pueblo. Through western Colorado it is 

 abundant in migration and in many places is the most com- 

 mon Warbler during the breeding season. Breeds very com- 

 monly along the eastern slope of the Rocky Mountains from 

 the foothills to 7,500 feet. Arrives the first week in May and 

 breeds about the middle of June. Leaves the State late in 

 September. 



646. Helminthophila celata. Orange-crowned Warbler. 

 Summer resident; not uncommon. Quite common in 



migration, extending over the plains and a little ways into the 

 mountains. Over the former it is known only as a migrant ; 

 in the latter it breeds from about 6,000 to 9,000 feet, but is 

 rare above 8,000 feet. Arrives the first week in May and leaves 

 late in September or early October. 



646a. Helminthophila celata [lutescens. Lutescent 



Warbler. 



Summer resident ; not uncommon. The western form of 

 the Orange-crowned Warbler, coming east as far as the eastern 

 base of the Rocky Mountains at Denver and at Colorado Springs. 

 Movements and habits so far as known the same as the Orange- 

 crowned Warbler. There is no doubt that the two forms occur 

 in Colorado, and that in general one inhabits eastern Colorado 

 and the other western, but whether their habitats meet or over- 

 lap, and their relative distribution in the mountains during the 

 breeding season, are points that need further elucidation. 



647. Helminthophila peregrina. Tennessee Warbler. 

 Migratory ; rare. Only known from eastern Colorado at 



the base of the Rocky Mountains, where it has been taken in 

 El Paso County by Aiken, at Boulder by Minot, at L,oveland by 



