Wilson's Warbler 469 



In Colorado the Pileolated Warbler is a common summer bird 

 throughout. Arriving from the south about the first week in May, it 

 quickly moves up from the plains and foothills to the higher elevations, 

 and nests from 7,000 to 12,000 feet, but chiefly at about 10,000 feet. 



Spring migration records are as follows : Monon, Baca co., May 

 3rd (Warren), Fort Lyon, May 5th (Cooke), El Paso co., May 14th, 

 and Limon, May 21st (Aiken), Denver May 14th (Henshaw), and 

 Loveland, May llth-13th (Cooke). Fall records are: El Paso co., 

 September 27th (Aiken), Pueblo, October 5th (Beckham), and Sapanero, 

 Gunnison co., September 26th (Warren M.S.). Breeding records are : 

 above timber hne near Idaho Springs, July (Trippe) ; Hancock, Chaffee 

 CO., 10,000 feet (Mrs. Stone), Seven Lakes, on the slopes of Pikes Peak; 

 about 11,000 feet, Jime 22nd (Minot) ; Fort Lewis, La Plata co., 7,500 

 feet (Morrison). 



Habits. — ^A sprightly and active little bird, this Warbler 

 is generally to be found about willow swamps at high 

 elevations ; it flits from bush to bush, and seldom perches 

 on trees. Its song is not remarkable, and is syllabled 

 by Minot " chee-chee," seven times repeated. The 

 nest is usually placed on the ground under the shelter 

 of a willow or other bush, though Morrison states that 

 he found it building in the cotton-woods and willows 

 that fringe the Rio de la Plata. The nest taken by Mrs. 

 Stone on July 16th contained two young birds ; it was 

 placed on the ground under a \\dllow, and was a flimsy 

 affair made of bark strips, rootlets and dried grasses, 

 and lined with a few horsehairs. The eggs, four or five, 

 are white or sometimes creamy, spotted and speckled 

 with browns and greys, sometimes regularly throughout, 

 sometimes in a wreath at the larger end. They average 

 •63 X "49. Gale gives June 12th to 25tb for fresh eggs 

 at Duck Lake, near Gold Hill, at 9,000 feet. 



Wilson's Warbler. Wilsonia pusilla. 



A.O.U. Checklist no 686 — Colorado Records — Ridgway 01, pt. ii., 

 p. 710; Chapman 07, p. 274. 



Description. — Closely resembling the Pileolated, but averaging a 

 little smaller (wing 2-15 as against 2-25), and coloration paler and 



