Notes on the Plumage of North American Birds 



FORTY-FIRST PAPER 

 By W. DeW. MILLER 



(See Frontispiece) 



In all Wrens the sexes are nearly or quite indistinguishable in coloration. 

 The slight seasonal differences are due only to wear and fading. In its juvenal 

 dress the young bird is not strikingly different from the adult, and the first 

 winter plumage cannot be distinguished from that of older birds except by 

 slight differences in the wings and tail, which are not renewed at the post- 

 juvenal molt. 



Cactus Wren {Heleodytes brunneicapillus couesi, Fig. i). — Nestlings 

 (juvenal plumage) differ from birds in the first winter or subsequent plumages 

 in the much smaller and less intense black of the spots on the throat and chest. 

 The back is spotted rather than streaked with white, and the brown of the 

 nape is usually less reddish. With the assumption of its winter plumage the 

 young bird becomes like the adult. The worn summer plumage lacks the 

 smoothness of the fresh autumn dress, but is little affected by fading. 



Two forms of this species are found in the southwestern United States — 

 the Cactus Wren proper {H. b. couesi) from Texas to Nevada and California, 

 and Bryant's Cactus Wren {H. b. bryanti) on the Pacific coast of California and 

 northern Lower California. The latter is darker and browner, more con- 

 spicuously streaked with white above and with larger or more numerous black 

 spots below. Three other races occur in Mexico, one of them in the Cape 

 Region of Lower California. 



Caiion Wren {Gather pes mexicanus conspersus, Fig. 2). — The nestling 

 plumage is similar to that of the adult, but the spots of the upperparts are 

 obscure, and the brown of the belly duller and usually immaculate. Subse- 

 quent plumages are all very similar to that of the first winter. 



The Canon Wrens inhabit the greater part of Mexico and the western por- 

 tion of the United States. Varying slightly in size and coloration in different 

 parts of this area, they are, like the Cactus Wrens, divisible into several geo- 

 graphic races. One of these is exclusively Mexican, while three are found in 

 the United States. The White-throated Wren (C. m. albijrons) is chiefly 

 Mexican, barely reaching our limits in western Texas. The Canon Wren (C. 

 m. conspersus) of the Great Basin and Rocky Mountain region is considerably 

 smaller than the preceding; and the Dotted Canon Wren (C. m. punclulatus) 

 of the Pacific coast region, while equally small, is decidedly darker in color. 



Carolina Wren (Thryothorus ludovicianus, Fig. 3). — When it leaves the 

 nest, the young Carolina Wren scarcely differs in color from the adult, but is 

 somewhat paler. The summer plumage is less richly colored than the fresh 

 fall dress, especially below, where the deep buff or cinnamon fades almost to 

 white before the annual molt. 



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