94 NOETH AMERICAN FAUNA. [no. 19. 



a dead tree about 150 yard« away, pouriiif^ forth this vohiinc of melody 

 without leaving- its perch. The siuger came close enough later to 

 make identification certain. 



Osgood and Maddren saw one at Lake Lcbarge Jul}^ 14, Osgood 

 took an adult at Miles Canyon July 11, another at the Semenow Hills 

 July 20, a young in the spotted plumage 20 miles below the Selwyn 

 River July 29, and another 3^oung 30 miles above the White River 

 July 30. I saw an adult near the Selw3"n River Jul}^ 29, and took a 

 molting adult near Sixty-Mile Creek August 1. Mr. Cantwell found 

 this species in the Yukon Valley. 



164. Hylocichla alicise. Gray-cheeked Thrush. 



Several thrushes which we heard singing on the west shore of Lake 

 Marsh July 8 were, I think, this species, as their song differed from 

 that of the dwarf, hermit, and Alma thrushes. 1 saw two, but they 

 were so shy that 1 could not secure either. Near Sixty-Mile Creek, 

 July 31, 1 took a young in spotted plumage, which was with the young 

 of almm which Osgood shot. At Circle I took a young in first winter 

 plumage, also with alnuB. 



165. Hylocichla ustulata almse.^ Alma Thrush. 



This is the common thrush of the Yukon basin, occurring every- 

 where from Log Cabin to Circle, perhaps in largest numbers at 

 Caribou Crossing and Lake Marsh. Fifteen miles above Fort Yukon 



1 took one, and saw others August 21, We found many nests, 

 usually 6 to 10 feet from the ground in thick growths of young 

 spruces, but none contained eggs. A nest containing four young 

 just hatched, which I found at Caribou Crossing June 25, was about 

 8 feet from the ground in a thicket of small spruces. The nest resem- 

 bled that of //. u. swainsoni. At Miles Canyon July 11 we saw 

 young able to fly. Osgood took young in spotted plumage July 31, 

 but those taken August 20 had assumed first winter plumage. 



They were usually silent by day, but sang frequently during the 

 short nights. At Caribou Crossing, the last of Juno, their song could 

 be heard constantly from 8 p. m. to 8 a. m., one taking up the 

 strain as another stopped. The song is much superior to that of 

 Hylocichla aonalaschkca and almost equal to that of TI. fuscescens. It 

 has whispered notes like that of H. mustelinus. By the middle of 

 July the song season was practically over, though we heard one of 

 the birds singing July 23. When the nights became really dark in 

 August, I often heard the call-note of this bird near our camp between 



2 and 3 a. m. 



1 Auk, XVII, 119, April, 1900. 



