Vol. XXXII 



1914 



] Rockwell and Wetmore, Birds of Golden, Colorado. 333 



They were very restless and flew back and forth across the ridges and were 

 usually rather wild. The moult began the last of July and bj^ the middle 

 of September specimens in full plumage were taken. At this date we found 

 flocks of young probably of the last brood scattered among the bushes 

 between six and seven thousand feet, while on top there were similar flocks 

 in full winter plumage. It was also noticed that during the spring the birds 

 of the plains level that bred early assumed the summer plumage at the same 

 time, while the birds in the mountains did not change for nearly a month 

 later. During October Western Robins were found in the gulches in large 

 flocks, feeding on haws and thorn apples. 



107. Sialia sialis sialis. Bluebird. — A single bird taken at the foot 

 of Dead Man's Gulch, May 2, was the only one seen. They appear to be 

 rare in this locality, though there are numerous records of their occurrence 

 in the state. The present bird — an adult female — averages a trifle paler 

 than Kansas specimens, but agrees with them in measurements. 



108. Sialia mexicana bairdi. Chestnut-backed Bluebird. — A 

 pair collected June 6 on Lookout Mountain were the only ones seen. These 

 birds had a nest containing five incubated eggs, in a woodpecker hole in a 

 pine about 30 feet from the ground on a steep hillside at the edge of an open 

 pine grove. The cavity was about ten inches deep by three inches in 

 diameter and the eggs were laid on a very scant lining of fine inner bark, 

 quite neatly cupped. The nest did not resemble that of the Mountain 

 Bluebird in any particular. 



109. Sialia currucoides. Mountain Bluebird. — Fairly common 

 summer resident throughout the region, but not as abundant as at higher 

 altitudes. We found the first ones already mated April 25 and from then 

 on they were fairly common. A Mountain Bluebird built its nest in the 

 wall of the same cabin used by the Flicker noted above. The entrance to 

 the nest was less than two feet above the ground and the eggs themselves 

 rested in a cranny between the timbers about a foot below the opening. 

 This is undoubtedly one of the lowest bluebird nesting sites on record. 

 During August there were large flocks principally of young birds among the 

 pines at 7500 feet where they fed on the ground or caught insects on the 

 wing. The only note given was a low turr-r- similar to that of the eastern 

 bluebird. We collected quite a series of these young birds expecting to 

 find that part of them were *S. m. bairdi, but were disappointed in this. 

 During September we noticed occasional small flocks, but none were seen 

 after the first of October. 



