OCT., 1900.] BIRDS OF THE YUKON REGION. 85 



a willow swamp near the lake, and it was eoinposed of fine, diy g'rasses, 

 lined with feathers, covered externally with a thick coating- of living 

 moss. The eggs, which average 0.80 by 0.57 inches, are pale pea g-reen, 

 heavily mottled over the entire surface with reddish fawn color. At 

 Lake Marsh July 8 I took an adult female, and 15 miles above Circle 

 August 8 a young bird molting from the striped juvenile into the fall 

 plumage. The species was abundant at Circle, and a number were 

 seen on an island 15 miles above Fort Yukon August 21. I saw one 

 at the Aphoon mouth August 27, and noticed seven during September 

 at St. Michael, taking the last Septeml)er 21. 



126. Spizella socialis arizonse. Western Chipping Sparrow. 



We found this species almost dail}^ from Log Cabin to Dawson, or 

 between June 15 and August 1. In point of numbers it follows the 

 intermediate sparrow and the slate-colored junco. It was last observed 

 ^bout 10 miles below Dawson August 3, but the range of the species 

 may extend much farther north, as a large flock seen near the Selwyn 

 River July 29 showed that the fall migration had l^egun. 



We found a nest with four eggs at Lake Bennett June 24, large 

 young in a nest on Lake Tagish June 30. Young able to fly were met 

 with at Lake Marsh July 5, and a set of three eggs on Thirty-Mile 

 River July 18. The nests were in small spruces, one 4 inches and 

 another about 3 feet from the ground. 



Yukon chipping sparrows, females especially, average darker than 

 typical aris(m<e, but coincide in measurements. Turner reports this 

 species from Fort Yukon, ^ 



127. Junco hyemalis. Slate-colored Junco. 



From Log Cabin to Circle this bird occurs ever3^where, contest- 

 ing with the intermediate sparrow for supremacy in numbers. Two 

 broods are, I think, regularly reared. Females taken at Log Cabin 

 and Bennett had finished laying. On Windy Island June 30 1 shot 

 a young bird aljle to fly, and on the east shore of Lake Tagish 

 the following day saw one pair building a nest and another feeding 

 young. Maddren found a nest with four fresh eggs at Lake Marsh 

 July 4:, Osgood one with three fresh eggs at Lower Lebarge July 16, 

 and I one with five young on Thirty-Mile River July 18, and another 

 with four just hatched young near the Tatchun River July 23. By 

 rluly 20 young in striped plumage were common, and August 2 I took 

 one near Dawson molting into first winter plumage. The slate-colored 

 junco, the intermediate sparrow, and the western chipping sparrow 

 were most common about brush heaps left by lumbermen, weed-grown 

 clearings resulting from forest fires, and cabins of the towns. Every 

 nest found was sunk in the ground to the rim in an open place 



'Contril). Nat. Hist. Alaska, 174. 1886. 



