88 General Notes. [Jj* 



June, 1902, I observed several pairs about the farm in Boulder County 

 and took two specimens. I say 'pairs' because they were thus found 

 and not in flocks. 



Catherpes mexicanus conspersus. Canon Wren. — Somewhat common 

 constant resident, through the lower foot-hill elevations of Boulder County. 

 That this species has been persistently overlooked, I can only account for 

 by the fact of their being such an early spring breeder. 



While investigating the nests of two pairs of Golden Eagles on March 

 27, 1907, I was agreeably surprised to find a pair of these wrens conveying 

 nesting material to a ledge in a small canon. With snow in abundance 

 on the north slopes, I sat in the sun and watched them for over two hours. 

 As this was my first acquaintance, I shall never forget the impression 

 made by the volume and clear, whistle-like effect of their few notes, — not 

 shrill, but filling the canon with a volume and penetration out of propor- 

 tion to a bird so small. I returned to this locality one week later, April 4, 

 1907, and found the nest completed, but containing only three eggs, which 

 we did not disturb. The nest was in a sheltered crevice, on a rock pro- 

 jecting from the face of a sixty foot cliff. My young friend went down a 

 rope to the site, from above; the only possible way of reaching it. Mr. 

 Brunning, at whose placed was staying, mentioned three localities in which 

 were the nesting sites of this wren. One, an upper ranch (altitude 7000 

 feet), and two near-by mining locations on which he worked at odd times 

 during the year. He states that "the birds would appear each year about 

 Thanksgiving time, remain all winter and through the spring but disap- 

 pear during the summer." It did not occur to him to make note of their 

 time of leaving, until he realized they were gone (a common difficulty 

 with fall migration data). 



Such an early nesting date, has been equalled or exceeded only by three 

 species in northern Colorado, viz., the Mexican Crossbill, Great Horned 

 Owl and Golden Eagle. 



Thryothorus bewickii bairdi. Baird's Wren. — Has been taken 

 nesting in the Naturita Valley, southwestern Colorado, by C. H. Smith, 

 a reliable observer, who reports it as "not common in his locality." — 

 Fred. M. Dille, Denver, Colo. 



