188 BULLETIN 196, UNITED STATES NATIONAL MUSEUM 



winters over much of South America east of the Andes, and is a 

 common spring and fall transient in Central America, unrecorded from 

 the Pacific slope north of Costa Rica. * * * Its supposed winter- 

 ing in Central America is based on assumption, and there is not a 

 single critically determined specimen on record in this country 

 [Guatemala], collected in January or February." 



HYLOCICHLA USTULATA ALMAE Oberholser 



WESTERN OLIVE-BACKED THRUSH 



HABITS 



Although the western olive-backed thrush was described many 

 years ago, it was not until within comparatively recent years that it 

 was admitted to our Check-list in the nineteenth supplement (Auk, 

 vol. 61, p. 457). 



In naming this race, Dr. Harry C. Oberholser (1898) gives a very 

 full and detailed description of it and then remarks: "The present race 

 differs from the eastern Hylocichla ustulata swainsonii in the more 

 grayish, less olivaceous color of the upper surface, this being most 

 noticeable on the rump and upper tail-coverts. The sides and flanks 

 also average more grayish. No apparent difference in size exists. 

 No comparison with H. ustulata proper is necessary, for Hylocichla u. 

 almae, although geographically intermediate, is even less closely allied 

 to ustulata than is swainsonii. * * * 



"Alma's Thrush is a common bird in eastern Nevada, where it 

 inhabits the growth of trees and bushes that fringe the mountain 

 streams. In the Monitor and East Humboldt Mountaius, it is 

 apparently the most numerous species of the family." 



We have no reason to think that the habits of this thrush differ 

 materially from those of neighboring races that five in similar en- 

 vironments. 



HYLOCICHLA MINIMA MINIMA (Lafresnaye) 



GRAY-CHEEKED THRUSH 



HABITS 



The gray-cheeked thrush spends the summer farther north than 

 any of our eastern thrushes, up to the tree limit and even beyond that 

 point nearly or quite to the Arctic coast of the far northwest. Dr. 

 E. W. Nelson (1883) describes its summer haunts in northern Alaska, 

 as follows: 



In middle latitudes where our acquaintance is made with this bird we associate 

 it with damp woodlands and sheltered glens, and it would seem almost incongruous 

 to one familiar with it in such surroundings to look for it as an inhabitant of the 

 barren stretches of arctic lands where for many miles not a tree raises its shaft 



