416 Birds of Colorado 



Distribution. — Breeding in favourable situations throughout the 

 greater part of Xorth America as far north as the Yukon Valley, and 

 south through north-west Mexico to Mazatlan ; south in winter as far 

 as Honduras and perhaps to South America. 



The Cliff-Swallow is a common summer bird in Colorado, breeding 

 locally from the plains to about 10,000 feet (colony at Fairplay in South 

 Park, 9,800 feet, Allen 72). They reach Colorado from the south about 

 the beginning of May — Canon City April 27th, Aiken (Henshaw 75), 

 Pueblo May 8th (Lowe), but do not breed before Jmie, and leave again 

 early in September. They have been recorded from all over the State, 

 from Weld co. (Marlcman), Limon (Aiken), and Baca co. (Warren 06) 

 on the eastern plains ; from Estes Park (Kellogg), Twin Lakes (Scott), 

 and Fort Garland (Henshaw), on the eastern slope ; and from Routt 

 CO. (Warren 08), Red-cliff (Keyser), and La Plata co. (Gihnan) on the 

 western slope of the Divide. 



Habits. — The Cliff -Swallow breeds in colonies, either 

 on vertical or overhanging cUffs along rivers or, perhaps 

 more frequently since the advent of man, on the waUs 

 or under the eaves of barns or outhouses. The nest 

 is built up of peUets of mud partially no doubt moistened 

 and softened by the saHva of the bird, and is usually 

 in the shape of a squat bottle, Avith the opening in front, 

 at other times hke a retort, with an opening at the top 

 of the nest, and a passage leading and opening down- 

 wards ; the nest so formed is lined with feathers, straw, 

 paper, leaves, or other soft material ; four or five eggs 

 are laid about June 5th in the plains, about a fortnight 

 or three weeks later in the mountains. A set of three 

 eggs, taken by I. C. HaU on June 15th, near Gteeley, 

 are rather long-ovals in shape ; they are white, moderately 

 spotted with two shades of brown, and average '87 x "55, 

 Like other SwaUows, these birds feed entirely on the 

 wing, chiefly on smaller insects, and are seldom seen 

 on the ground, as their legs are very small and weak. 



Genus HIRUNDO. 



Moderate-sized Swallows — wing less than 5-0 — with bill like that of 

 Petrochelidon but slightly longer ; nostrils narrow, elongated, opening 



