Notes on the Plumage of North American Sparrows 



TWENTY-SIXTH PAPER 



By FRANK M. CHAPMAN 



(See Frontispiece 



Cassin's Purple Finch {Carpodacus cassini, Figs, i and 2). This western 

 species resembles the Purple Finch, but is somewhat larger and has the bill 

 slightly longer and more regularly conical — that is, less bulbous at the base. 

 In color, the male is paler than the male of the Purple Finch, particularly on 

 the underparts, the back is more broadly and heavily streaked, and the red 

 of the crown appears as a more or less well defined cap. Between the females 

 of the two species the differences in plumage are less apparent, but in Cassin's 

 the streaks on the underparts are darker and much more distinct. 



The plumage changes of Cassin's Finch appear to be the same as those of 

 the Purple Finch. That is, the juvenal or nestling plumage resembles in pat- 

 tern and color the succeeding or first winter plumage, in which the male 

 cannot be surely distinguished from the female. 



This plumage is worn during the first breeding season, at the end of which 

 it is lost by post-nuptial molt, and the pink plumage of maturity is acquired. 



There is no spring molt, and the differences in the appearance of summer 

 and winter birds are due to wear which makes females and young males look 

 more sharply streaked, while adult males, as was explained under the Purple 

 Finch in Bird-Lore for February, seem brighter. 



House Finch {Carpodacus mexicanus frontalis, Figs. 5 and 6). The House 

 Finch, or 'Linnet,' is one of the commonest birds of the western United States, 

 and lives even in large cities, where, in places, it is as familia/ as the House 

 Sparrow. Its differences from the Purple Finch are clearly shown by Mr. 

 Fuertes' plates, and need not be dwelt on here. The plumage changes appear 

 to be the same as those of the Purple Finch, but the differences between 

 summer and winter plumage are more pronounced than in that species, the red 

 areas in the adult male being much deeper and brighter in summer than in 

 winter. 



This member of the genus Carpodacus is responsive to the influences of its 

 environment, and hence shows more or less geographic variation which has 

 resulted in the recognition of several geographic races or subspecies. Three of 

 these are confined to Mexico, and five are found within the limits covered by 

 the 'Check-List' of the American Ornithologists' Union. They are (i) the 

 House Finch of the western United States, mentioned above, and figured in 

 the frontispiece; (2) the San Lucas House Finch {Carpodacus mexicanus ruber- 

 rimus), of Lower California; (3) the San Clemente House Finch {Carpodacus 

 mexicanus dementis), of certain islands off the coast of Cahfornia from Santa 

 Barbara southward; (4) Guadalupe House {Carpodacus amplus. Figs. 2 and 3), 

 of Guadalupe Island; and (5) McGregor's House Finch, of San Benito Island. 



(107) 



