2l8 UNIVERSITY OF COLORADO STUDIES 



Mimus polyglottos leucopterus, Western Mockingbird (703a) 



Summer resident; rare on the Plains. In the spring it has been seen May 15 

 (Gale) and May 17 (Henderson). Gale found a few nests, May 31, 1886, and 

 June 1-10, 1887. It was not observed by the writer. It is apparently more 

 common both east and northeast of the county — near the Barr Lakes and toward 

 Ft. Collins. 



Dumetella carolinensis, Catbird (704) 



Summer resident; common on the Plains and in the Yellow Pine zone. 

 Arrives, May 8-15 (4 records); leaves, September 14-20 (3 records). Gale 

 found eggs between June 1 and July 3. Widmann observed it at Estes Park (7,500 

 feet). 



Toxostoma rufum, Brown Thrasher (705) 



Summer resident; rare on the Plains. Arrives, May 5-15 (3 records); no 

 fall dates available. Gale found a nest with four eggs on June 25, 1883, and 

 several nests, May 31, 1886. The writer saw a pair, July 21, 191 2. Henderson 

 recorded one seen in the county. 



Family TROGLODYTIDAE, The Wrens 



Salpinctes obsoletus obsoletus, Rock Wren (715) 



Summer resident; occurs locally on the Plains, is common in the Yellow Pine 

 and occurs at least in the lower part of the Mountain zone at 9,000 feet. Arrives, 

 April 27 — May 8 (3 records); leaves, October 8-27 (3 records). Gale recorded 

 three nests found between June 1 1 and 24. 



Catherpes mexicanus conspersus, Canyon Wren (717a) 



Permanent resident; common in the canyons of the lower Yellow Pine zone. 

 Noted near Boulder Falls (in the upper part of the Yellow Pine zone) and, in 

 winter, at White Rocks, about seven miles out on the Plains. The writer found 

 a nest site which was occupied three successive years; young in the nest July 10, 

 1910, and July 23, 1911, and six eggs on May 8, 1912. Dille (Sclater) found a 

 nest with three eggs, April 4. 



Troglodytes aedon parkmani, Western House Wren (721a) 



Summer resident; rather common on the Plains, and common in the Yellow 

 Pine and Mountain zones. Arrives, April 28 — May 8 (5 records); leaves, Sep- 

 tember 11-22 (3 records). Birds have been seen nest-building as early as May 12, 

 and feeding young in the nest as late as July 23. Eggs have been found from May 

 26 to June 17. One nest in the University collection was labelled 10,000 feet by 

 Gale. 



