136 University of California Publications in Zoology [Vol.12 



Of the five specimens secured by us only one has the shafts and 

 under surfaces of the wings and tail yellow as in the two Cooper 

 specimens from Fort Mohave. Reference to literature shows that this 

 yellowness is generally supposed to be a constant character of chrysoides. 

 In fact I find but four recorded exceptions: Brewster (1883, p. 25) 

 mentions a specimen taken at Tucson, Arizona, as "having the yellow 

 of the wings and tail replaced by orange, while the shafts of many of 

 the feathers show an even stronger reddish cast, those of the rectriees 

 at their bases being especially deep in color." Brewster remarks fur- 

 ther that "this departure from the normal coloring undeniably nar- 

 rows the gap which separates chrysoides from mexicanus [=collaris] , 

 but it may be merely a chance reversion, or, what is perhaps still 

 more likely, the specimen in question may be a hybrid." Coues (1903, 

 p. 602) observes that "gradation between this form [chrysoides] and 

 C. mexicanus [=collaris] has not yet been observed." 



Swarth (1905, p. 27) discusses at length an aberrant specimen from 

 the Papago Indian Reservation, Arizona, evidently in the same cate- 

 gory as Brewster's. Swarth considers this a hybrid between chry- 

 soides and collaris, although he goes on to say that he found these two 

 species in that region "breeding almost side by side, practically 

 without mixing," and this seems strange "when we consider the 

 extensive hybridization that takes place in the northwest, where 

 collaris and luteus come together." 



Breninger (1898, p. 13) reports two supposed hybrids between the 

 "gilded" and "red-shafted" nickers. But these are probably of the 

 same nature as Brewster's and Swarth 's. 



The abnormal appearance of four out of five of the flickers col- 

 lected by us on the lower Colorado, and the circumstance that this 

 abnormality consists in a redness approximating the color of corres- 

 ponding areas in collaris, led us to conclude at the time that we had 

 there found chrysoides and collaris hybridizing. The chief characters 

 of the specimens in question are shown in an accompanying table ; also 

 the corresponding characters of those examples of collaris taken by 

 us in the Colorado Valley. The latter, it should be emphasized, are 

 believed to have been winter visitants to the region, and not repre- 

 sentative of the breeding species. 



No. 12761, male of typical yellow chrysoides, and no. 12762, female 

 with under surfaces of wings and tail coral red, were a mated pair, 

 the parents of the young found in a saguaro on the California side. 

 These young, preserved as alcoholics, are in too early a stage for the 



