THE OALIiPOENIA CUCKOO. 27 



The eggs of the California Cuckoo are usually three or four in number. 

 They are light greenish blue in color, unspotted, and in time this unstable tint 

 fades to a uniform pale yellowish green. They are mostly elliptical oval in 

 shape; a few maybe called elliptical ovate, one end being slightly more pointed 

 than the other. The shell is fine grained, rather thin, and without gloss. The 

 eggs average a trifle larger than those of the Yellow-billed Cuckoo. 



The average measurement of forty -three specimens in the United States 

 National Museum collection is 30.85 by 23.16 millimetres, or about 1.21 by 0.91 

 inches. The largest of these eggs measures 33.53 by 24.38 millimetres, or 1.32 

 by 0.96 inches; the smallest, 27.43 by 21.08 milhmetres, or 1.08 by 0.83 inches. 



The type specimen, No. 20470 (PL 5, Fig. 2 ), Bendire collection, from a set 

 of four eggs, was taken by the writer on Rillito Creek, near Tucson, Arizona, on 

 July 27, 1&72. This is one of the largest eggs in the series, and is slightly 

 faded, fresh eggs looking somewhat brighter. 



9. Coccyzus erythrophthalmus (Wilson). 



BLACK-BILLED CUCKOO. 



Guculus erythrophthalmus Wilson, American Ornithology, IV, 1811, 16, PI. 28. 

 Coccyzus erythrophthalmus Bonaparte, Journal Academy Natural Sciences, Phila., Ill, ii, 

 1824, 367. 



(B 70, 290, R 388, C 428, U 388.) 



Geographical range: Eastern North. America; north in the Dominion of Canada 

 to Nova Scotia, New Brunswick, southern Quebec, and Ontario, to about latitude 47°, and in 

 the provinces of Manitoba and eastern Assiniboia to about latitude 51°; west in the United 

 States to the eastern foothills of the Rocky Mountains, Montana, Wyoming, Colorado, and 

 Texas; south, in winter, to the West India Islands, Central America, and northern South 

 America. Accidental in Great Britain and Italy. 



The Black-billed Cuckoo, a slightly smaller bird than the Yellow-billed, is 

 likewise known by the different local names of the latter, and is often mistaken 

 for it. It appears to be somewhat hardier, extending its migrations- several 

 degrees farther north, and it breeds throughout its range from about latitude 35° 

 northward. ' Occasionally it has been reported as breeding still farther south, 

 but below the latitude named it must be considered as an irregular and rare sum- 

 mer resident. In eastern North America it reaches the northern limits of its 

 range in about latitude 47°, while in the interior, in the provinces of Manitoba 

 and eastern Assiniboia, it has been found as far north as latitude 51°, and it 

 ranges probably still farther in this direction. The eastern slopes of the Rocky 

 Mountains appear to form the western limits of its habitat. Here it has been 

 obtained at Pryor's Fork of the Yellowstone, Montana, and I found it breeding 

 on the Little Horn River, near Fort Custer, on June 25, 1885. Mr. W. G. Smith 

 has observed it in Larimer County, Colorado, where he believes it breeds, but it 

 is rare. It is a fairly common species in suitable localities throughout the greater 

 part of its range, and in the more northern portions it outnumbers the Yellow- 



