212 UNIVERSITY OF COLORADO STUDIES 



Guiraca caerulea lazula, Western Blue Grosbeak (597a) 



Dille took two and saw others near Altona in June, 1902. Felger took one 

 in 1903 (Henderson). The writer saw one on the Plains, June 30, 191 2. These 

 appear to be the most northern records for the state. It is probably a regular 

 though rare visitant. 



Passerina amoena, Lazuli Bunting (599) 



Summer resident; infrequent on the Plains and common in the lower part 

 of the Yellow Pine zone. Arrives, May 8-r9 (4 records) ; leaves, August 7-29 

 (4 records). Gale observed nest-building on June 21 and found eggs, July 3. 

 A specimen in the University collection taken September 4, 1905, is labelled Camp 

 Albion (11,000 feet). 



Spiza americana, Dickcissel (604) 



Bragg collected one near Boulder in 1903. The writer observed a male in 

 two localities, July 9 and 24, 1910, and July 9 and 20, 191 1. Mr. and Mrs. T. A. 

 McHarg reported one seen at Lyons, August 12, 1912. It will be interesting to 

 note whether this species becomes established in the county as a regular summer 

 resident, as in the case of the Bobolink. 



Calamospiza melanocorys, Lark Bunting (605) 



Summer resident; abundant on the dry mesas of the Plains. Arrives, May 

 10-17 (4 records) ; leaves, August 27 — September 12 (3 records). Eggs have been 

 found between June 1 and 22. 



Family TANGARIDAE, The Tanagers 

 Piranga ludoviciana, Western Tanager (607) 



Summer resident; rather common in the Yellow Pine zone. Gale stated that 

 it was to be found up to 10,000 feet. Arrives, May 5-16 (6 records); leaves, 

 September 30 — October 10 (2 records). Gale took a set of four eggs on June 17 

 at about 8,500 feet. 



Family HIRUNDINIDAE, The Swallows 

 Petrochelidon lunifrons lunifrons, Cliff Swallow (612) 



Summer resident ; abundant in the Plains and Yellow Pine zones and occurring, 

 at least in migration, in the Mountain zone at 9,000 feet. Arrives, May 5 (1 

 record); leaves, August 13-28 (4 records). Nests nearing completion have been 

 noted May 21 and June 1 on the Plains. A former nesting-site on a cliff at 

 White Rocks appears to have been abandoned, and the birds are now nesting 

 commonly under the eaves of barns on the Plains. 



