October, 1846.] 113 



Troglodytes Bewickii, Aud. Bewick's Wren. 



Common, keeping in low bushes and piles of brush, as well as about old 

 dead trees and logs, over and around which it flits with the greatest ac- 

 tivity, uttering, when approached, the usual grating scold of the wrens. 



Troglodytes palustris, Wils. Marsh Wren. 



I found this species in small reedy marshes in the Rocky Mountains of 

 the interior, in October. 



Troglodytes sylvestris, Nobis. Audubon's Wood Wren. 



T. Americana^ Aud. Orn. Biog., vol. 2, p. 452, pi. 179. 



A summer resident among the evergreen oaks of California, in which 

 it sings and breeds. 



I have changed the name of this species from that given by its discoverer, 

 because that a Troglodytes Americanus, from Cayenne, was described by 

 Cuvier, in the Gal. du Paris. See Lesson's Traite de Ornithologie, p. 400. 



Sial, artica, Swains. Artie Blue bird. 



This beautiful azure songster is common throughout the northern pro- 

 vinces of Mexico. In the neighborhood of Santa Fe it is abundant, keeping 

 about the houses and gardens where they breed, sometimes forming its 

 nest in boxes which are stuck up for the purpose by the inhabitants. In 

 the ranges of the Rocky Mountains, as far as California, we frequently found 

 it, and always associated with the S. Mexicana, both at this season occa- 

 sionally uttering their cheerful song to remind us of home. 



Sialia Mexicana, Swains. Western Blue bird. 



S. occidentalis, Townsend, Aud. 



This species is found throughout the Rocky Mountains, in company with 

 the former, and in California is by far the most abundant species. In 

 April and May, I found it breeding in the knot holes of the evergreen 

 oaks. During winter they assemble in small flocks, and frequent the 

 weedy plains and valleys of the mountains. 



Turdds migratorius, Linn. American Robin. 



We found the Robin scatteringly throughout the Rocky Mountains, and 

 a few are found at all seasons, in California. 



Tukdus nosvius, Gmel. Varied Thrush. 



I have only observed this beautiful species to pass through California 

 during the spring and autumn, in silent flocks. 



Tordds minor Gmel. Hermit Thrush. 



T. nanus. Dwarf Thrush. Aud. Orn. Biog. 5, p. 204, pi. 419 ; Nutt. 



Man. p. 396. 

 T. solilarius. Auc. 



The confusion hitherto existing in the description of the nearly allied 

 group of Thrushes to which this belongs, has rendered the determination 

 of the species exceedingly difficult, and at best but a matter of uncertainty, 



