191-4] Grinnell: Mammals and Birds of the Colorado Valley 153 



The above are the measurements and features of coloration which 

 I find of diagnostic value, in discriminating these three flycatchers. 

 They apply satisfactorily to the transient flycatchers of Arizona and 

 California. Hut the breeding- ranges of these forms west of the Rockies 

 are still imperfectly made out and there is undoubtedly extensive con- 

 fusion in the literature. 



Empidonax griseus Brewster 

 Gray Flycatcher 



With very little doubt this flycatcher is a winter visitant ; but it 

 was nowhere common. The first one noted was shot February 22, on 

 the California side five miles below Needles. The next was secured 

 March 10, also on the California side, in Chemehuevis Valley. Three 

 were taken on the California side near Riverside Mountain ; two on 

 the same side opposite Cibola ; and two on the Arizona side ten miles 

 below Cibola. The last two were taken April 6 and 7. Nothing more 

 was seen of the species after the latter date. Of the nine examples 

 secured by us (nos. 12S74-12882) all are males. This may be indic- 

 ative of separate areas of wintering for the two sexes, or at least that 

 those individuals wintering farthest north are males. 



Two specimens (nos. 4300, 4301) taken by J. G. Cooper at Fort 

 Mohave, April 11 and 27, 1861, are also males. 



Pyrocephalus rubinus mexicanus Sclater 

 Vermilion Flycatcher. 



An adult male seen at Needles, California, February 14. A few, 

 not more than six in all. noted March 27 to 29 in the vicinity of 

 Ehrenberg, Arizona, where they remained in the sparse mesquite growth 

 at the margin of the bottom farthest from the river. Fairly common 

 April 1 to 5 on the California side opposite Cibola, where closely con- 

 fined to a narrow strip of mesquite close to the river and along a 

 Lagoon. Here a nest was found, April 2, containing three eggs in 

 which incubation was far advanced. It was fifty-four inches above the 

 ground, saddled on the bare forking branch of a dead mesquite stand- 

 ing in an open area thirty-five yards from the river bank. 



The nest (no. 767) is slight in bulk, but firmly constructed, mainly 

 of straight short dry twigs held together and to the large supporting 



