THE WHITE-BELLIED SWALLOW. 257 



species ; and, in fact, identification is next to impossible. 

 In a majority of the present species, the spots are somewhat 

 coarser j and the eggs are generally longer. Four eggs, 

 collected in Dorchester, Mass., are of the average dimen- 

 sions of .84 by .54 inch ; other specimens, from various 

 localities, are about this size. 



Like the Barn Swallow, this species gathers into large- 

 flocks at the end of the summer, and frequents the same 

 localities, but not at the same time ; as it leaves usually a 

 week or ten days before the other bird. 



HIRUNDO BICOLOR. Vieillot. 

 The White-bellied Swallow; Blue-backed Swallow. )( 



Hirundo bicolor, Yieillot. Ois. Am. Sept., I. (1807) 61. Aud. Orn. Biog. (1831), 

 491. 



DESCRIPTION. 



Glossy metallic-green above; entirely white beneath. Female much duller in 

 color. 



Length, six and twenty-five one-hundredths inches ; wing, five inches ; tail, two 

 and sixty-five one-hundredths inches. 



This very common and well-known species is a summer 

 inhabitant of all New England ; being most abundant in 

 localities near sheets of water, and less common in high, 

 dry districts. Its habits are well known ; and arriving, as 

 it does, early in the season, and fraternizing with man, it is 

 a great favorite. It makes its appearance as early as the 

 first week in April, but does not commence building before 

 the middle of May. Near cities and towns, the nest is 

 built in martin-boxes provided for its reception : but, in 

 less thickly settled districts, it is built in holes in stumps 

 and trees ; and cases are on record of its being built in a. 

 deserted nest of the common Barn Swallow. When passing 

 through the chain of the Umbagog lakes, in Maine, I 

 observed great numbers of these, birds whose nests were 

 built in holes in dead trees standing in the lake near the 

 shores. These nests were so plenty, that, in the area of 

 17 



