BIRDS OF BOULDER COUNTY, COLORADO 21 5 



Family MNIOTILTIDAE, The Wood Warblers 

 Mniotilta varia, Black and White Warbler (636) 



One was observed at Boulder by Minot, June 1, 1880. Sclater gives but 

 four records for Colorado. 



Vermivora virginiae, Virginia's Warbler (644) 



Summer resident; common in the Yellow Pine zone, particularly where it 

 meets the Plains. Arrives, May 4-15 (2 records); leaves, September 17-21 

 (3 records). Widmann observed one in July at 8,000 feet near Estes Park, and 

 H. G. Smith (Sclater) found a nest in the same region placed on the ground under 

 a ledge, June 20. 



Vermivora celata celata, Orange-crowned Warbler (646) 



Migrant; probably rather common in the Plains and Yellow Pine zones. 

 Noted in the spring from May 4 to May 21, and in the fall, September 8-18. 

 It has been recorded from the county by Minot and one was taken by Bragg. A 

 specimen taken on September 18, 1910, by the writer was identified by Oberholser 

 as typical celata, though he believes the Rocky Mountain birds to be mainly ores- 

 lera, a form not at present accepted by the American Ornithological Union. 



Vermivora peregrina, Tennessee Warbler (647) 



Migrant; probably of regular occurrence on the Plains, though at present the 

 records are few. Seen in the spring, May 23 and May 31 (Minot), and in the 

 fall, September 25. 



Dendroica aestiva aestiva, Yellow Warbler (652) 



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

 Arrives, April 30 — May ii (7 records); leaves, August 14-28 (4 records). Gale 

 found eggs June 1-23. Widmann observed several pairs at Estes Park (7,300 feet) 

 and found a nest with eggs, June 24. 



Dendroica coerulescens coerulescens , Black-throated Blue Warbler (654) 



A specimen was found dead by J. J. Blanchard, October 16, 191 1, near Boulder 

 Creek in the Yellow Pine zone. This is the third record for Colorado. 



Dendroica coronata, Myrtle Warbler (655) 



Migrant; common in the spring on the Plains. Arrives, May 2-7 (3 records). 

 It has not been definitely recorded in the fall, possibly from confusion with the 

 Audubon's Warbler when in its fall plumage. 



Dendroica auduboni auduboni, Audubon's Warbler (656) 



Summer resident; infrequent in the upper part of the Yellow Pine and com- 

 mon in the Mountain zone. Arrives on the Plains, April 16 — May 7 (8 records); 



