178 ARCTIC BLUE-BIRD. 



Length to end of tail 7 inches; bill along the ridge ff , along the edge of 

 lower mandible yf; wing from flexure 4-f^; tail 2 T §; tarsus yf, hind toe y%, 

 its claw yz) middle toe yj, its claw y^. 



Adult Female in summer. 



The female differs from the male in the same degree as that of the Arctic 

 Blue-bird from its male; the upper parts being light greyish-brown, tinged 

 with blue, which is brighter on the rump; the wings and tail are as in the 

 male, but with less blue; the lower parts are bluish-grey, the breast and sides 

 light brownish-red, tinged with grey. 



ARCTIC BLUE-BIRD. 



7 Sialia arctica, Swains. 

 PLATE CXXXVL— Male and Female. 



This beautiful species, first introduced to the notice of ornithologists by 

 Dr. Richardson, who procured a single specimen at Fort Franklin, in July 

 1825, is merely a summer visitor to the Fur Countries. Both the male and 

 the female are represented in my plate. The latter I believe has not hitherto 

 been figured. Mr. Nuttall's notice respecting this interesting bird, so 

 closely allied to Sialia Wilsoni, is as follows: 



"Sialia arctica. Ultramarine Blue-bird. About fifty or sixty miles 

 north-west of the usual crossing place of that branch of the Platte called 

 Larimie's Fork, in the early part of June, this species of Sialia is not 

 uncommon. The female utters a low plaint when her nest is approached, 

 the place for which is indifferently chosen in a hole in a clay cliff, or in that 

 of the trunk of a decayed cedar. At this time the young were hatched. 

 The nest is made of the usual material of dry grass in very insignificant 

 quantity. They are more shy than the common species, and have the same 

 mode of feeding by watching on some low bush or plant, and descending for 

 an insect. We afterwards saw a nest of this species on a cliff of the Sandy 

 river, a branch of the Colorado of the West. The female and male were 

 both feeding their brood. The former chirped and appeared uneasy at my 

 approach, and at intervals uttered a plaintive yeow. The male sings more 



