420 Birds of Colorado 



Fresh eggs are to be met with between June 1st and 

 15th ; a full clutch is usually six ; the eggs are pure white 

 and unspotted. 



Genus TACHYCINETA. 



Closely allied to Iridoprocne, but distinguished by its shorter and 

 less forked tail, about i the length of the wing and forked for about 

 ■|- of its length, and by its shorter lateral toes, the claws of which fall 

 short of the base of the middle claw. 



This genus contains one species forming three geographical races, 

 and ranges over western North America as far south as Costa Rica. 



Violet-green Swallow. Tachycineia thalassina lepida. 



A.O.U. Checklist no 615 — Colorado Records — Allen 72, p. 149 ; 

 Trippe 74, p. 88 ; Henshaw 75, p. 217 ; Scott 79, p. 93 ; Minot 80, 

 p. 228 ; Stone 81, p. 67 ; Drew 81, p. 88 ; 85, p. 15 ; Allen & Brewster 

 83, p. 160 ; Beckham 85, p. 141 ; Morrison 88, p. 73 ; Kellogg 90, p. 89 ; 

 Lowe 92, p. 101 ; 94, p. 269 ; Cooke 97, pp. 19, 111, 217 ; McGregor 

 97, p. 39 ; Keyser 02, p. 207 ; Henderson 03, p. 108 ; 09, p. 238 ; Gihnan 



07, p. 194 ; Markman 07, p. 158 ; Warren 08, p. 24 ; 09, p. 17 ; Rockwell 



08, pp. 175, 195. 



Description. — Male — Above green, the head of a more mossy tinge, 

 the back more bronzy, the two shades separated by narrow purplish 

 collar, more or less conspicuous ; rump and upper tail-coverts mixed 

 metallic purplish and blue, with a conspicuous white patch on either 

 side at the base ; wings and tail dusky with a slight metallic gloss ; 

 below, including the ear-coverts and a patch above the eye white ; 

 iris brown, bill black, legs brownish. Length 4-75 ; wing 4-70 ; tail 

 1.90 ; CLilmen -20 ; tarsus -38. 



The female is duller than the male throughout ; tlie crown is a dull 

 brown, very slightly glossed with greenLsh, the ear-coverts and supra- 

 orbital patch are mottled grey, and the size is smaller— wing about 

 4-15. A yoimg bird is plain dusky above, the metallic gloss gradually 

 appearing, first on the middle of the back. 



Distribution. — Western North America, breeding from Alaska to 

 western Texas and New Mexico ; south in winter through Mexico 

 to the highlands of Costa Rica. 



In Colorado the Violet-green Swallow is a common summer bird, 

 though somewhat locally distributed, from the eastern foothills west- 

 wards. Arriving during the first half of May from the south, they 

 mostly go up into the moimtains to breed, and are chiefly met with 

 from 8,000 to 10,000 feet. They are specially common in the " parks." 

 They come down again in late Augast and leave for the south in 

 September. 



