Vol i909" VI ] Felger, Colorado Water Birds. 277 



4. Colymbus nigricollis californicus. American Eared Grebe. — 

 Summer resident; very common locally. (April-Oct. 22.) Breeds in 

 considerable numbers all along the Barr Lake Chain. Begins laying in 

 latter part of April or first part of May. The writer has found by May 19 

 sets of as many as eight and nine eggs advanced in incubation. In all of 

 the sets incubation had at least begun, but in the majority it was from 

 one fourth to three fourths complete. 



6. Podilymbus podiceps. Pied-billed Grebe. — Summer resident; 

 very common locally. This species is usually found associated with the 

 former, and in many cases in almost equal, if not equal, numbers. The 

 remarks made in regard to the former species will apply equally to this 

 species. 



7. Gavia immer. Loon. — Migrant; rather rare. (March ?, April 15- 

 May 7; Sept. 18-about Dec. 1.) Seen oftener in fall than in spring, 

 usually in ones or twos, but the writer has one record of five in a flock. 

 George C. Welch shot one on the Barr Lake Chain, and the writer has two 

 that were shot by B. T. Ames in the same locality. Of the nineteen 

 records that the writer has for this area and adjoining and near-by areas, 

 fourteen are noted for the fall. 



[8. Gavia adamsi. Yellow-billed Loon. — Migrant; very rare in 

 adjoining area. (May 25, only date.) One specimen, the only record for 

 Colorado, was taken by W. G. Smith, May 25, 1885, near Loveland. (Birds 

 of Colo., p. 155.)] 



[37. Stercorarius parasiticus. Parasitic Jaeger. — Migrant; very 

 rare in adjoining localities. (Fall to early winter.) There was one in the 

 Maxwell collection, taken at Boulder in December of some year prior to 

 1874; reported by Cooke. (Birds of Colo., p. 50.) H. G. Smith reports 

 one at Sloan's Lake in the fall of 1889. (Nid., Ill, 1896, p. 48.)] 



[40. Rissa tridactyla. Kittiwake. — Migrant; very rare in adjoining 

 and near-by areas. (December, only month recorded.) One, the only 

 specimen for Colorado reported to date, was in the Maxwell collection and 

 was taken at Boulder in December; reported by Cooke. (Birds of Colo., 

 p. 50.) Rudolph Borcherdt, a Denver taxidermist, stated to me on Feb. 3, 

 1906, that he had received one or two of this species to mount during his 

 residence in this city.] 



[49. Larus occidentalis. Western Gull. — Straggler from the West; 

 very rare in adjoining area. (September, only month reported.) One 

 taken by Prof. Wm. Osburn, at Loveland, Sept. 30, 1889; reported lay 

 Cooke. (Birds of Colo., p. 50.)] 



51. Larus argentatus. Herring Gull. — Migrant; rather uncommon. 

 (March-December.) As a rule associated in small numbers with Ring- 

 billed Gulls, but sometimes in small flocks by themselves. Eight birds 

 is the most that I have ever seen together here. One may expect to see an 

 occasional specimen at any time when the Ring-bills may also be found. 



[53. Larus californicus. California Gull. — Straggler from the West ; 

 very rare in adjoining area. (May, only month reported.) One taken 

 by Prof. Wm. Osburn, at Loveland, May 7, 1890. (Birds of Colo., p. 51.)] 



