TREE SWALLOW. 339 



In Alaska it is found along the south-eastern coast, extending 

 thence over nearly the entire Aleutian chain, and north along the 

 coast of the mainland to Kotzebue Sound, and thence throughout the 

 territory wherever suitable situations occur. 



Genus TACHYCINETA Cabanis. 

 TACHYCTNETA BICOLOR (Vieill.). 



1^48. Tree Swallow. (6U) 



Lustrous green ; l)elow, pure white. Yonii;/ : — Similar, not so glcssy. 

 Length, 6-<ih ; wing, ") ; tail, 2^. 



Hab. — North America at large, from the Fur Countries southward, in 

 wintei- to the West Indies and Central America. 



Nest, of leaves and grass, lined with down and feathers. 



Eggs, foiii' to seven, white, unspotted. 



A common summer resident, arriving early in May and leaving 

 about the middle of September. 



The White-bellied Swallows must at times have considerable 

 trouble in finding suitable places for their summer abode, but it 

 may be that, like people who move often, they have come to enjoy 

 the occupation of house-hunting. The original nesting place was a 

 hole in a tree or stub near water, but as the birds ai-e incapable 

 of making such an excavation themselves, they had to search for 

 a natural aperture, or the deserted hole of a woodpecker to suit 

 their purpose, the finding of which must have been to some extent 

 accidental. As the country became settled, and the swallow trees 

 were cleared away, the birds betook themselves to breeding in boxes, 

 which in the east were put up in great numbers for their accommo- 

 dation. On the advent of the English Sparrow, many pairs of 

 swallows were summarily ejected from their boxes, and were obliged 

 to retire to the remote parts of the country, and resume their 

 primitive habit of nesting in trees. On this account they are not so 

 common in towns and villages as they were some years ago, but are 

 more generally distributed throughout the countiy. In Southern 

 Ontario they are seen in greatest numbers during the season of 

 migration. 



This species is reported as common in Manitoba and the North- 

 West, and reaches its northern limit in Alaska, where its distribution 



