in Various Species of North American Birds. 
63 
Unquestionably it is abnormal, but hardly to be placed in a category with 
albinism, and probably it is not very unfrequent. Adult males of P. 
rubra change to the greenish autumnal plumage of the female and young, 
a fact not generally known. They may in that stage be distinguished by 
the blacker coloring of the wings and tail. I have never seen the young- 
males in autumn with red feathers appearing in the plumage, as spoken of 
by writers ; probably such specimens may be referred to adult birds taken 
in August or September, with the moult only partially effected ; many of 
such examples I have now before me, all unquestionably adults. The 
scarlet bands on the wing-coverts of some specimens are to be regarded as 
individual adornments, independent of age. Many comparatively imma- 
ture specimens possess them, while in some of the finest birds they are 
wanting. 
43. Hirundo horreorum. 
First plumage : female. Fork of tail not deep ; outer feathers project- 
ing one-half inch beyond the inner ones. Remiges and rectrices brown ; 
upper parts, in general, glossed with dull steel-blue ; feathers of rump 
and upper tail-coverts edged with rusty ; frontal band narrowed to a mere 
line of pale fawn-color. Beneath similar to adult, but everywhere paler. 
From a specimen in my collection taken at Rye Beach, N. H., August 21, 
1872. 
44. Tachycineta bicolor. 
First plumage : male. Upper parts uniform dark slate, with a fine silky 
gloss ; feathers of interscapular region faintly edged with pale fawn. 
Secondaries edged and tipped with pale cinnamon-gray. Under parts 
soiled white, with a faintly indicated pectoral band of pale ashy-brown. 
From a specimen in my collection, shot at Cambridge, June 22, 1872. 
A good series of summer specimens shows well the transitional stages. 
The first plumage is worn much longer than in most birds, and the au- 
tumnal dress very slowly acquired, the metallic tinted feathers appearing 
one or two at a time. The remiges are also moulted by the young, as well 
as by the adult, and both in the autumnal plumage have the last pair of 
secondaries broadly tipped with pure white. This remarkable feature, so 
far as the specimens at hand go to show, is entirely characteristic of this 
plumage. 
45. Petrochelidon lunifrons. 
First plumage : male. Top of head, back, and scapulars dark brown ; 
collar around nape, dull ashy, tinged anteriorly with rusty. Rump as in 
adult, but paler ; forehead sprinkled with white, and with a few chestnut 
feathers. Secondaries broadly tipped with ferruginous. Throat white, a 
few feathers spotted centrally with dusky. Breast and sides ashy, with a 
rusty suffusion, most pronounced on the latter parts. A very small area 
of pale chestnut on the cheeks. From a specimen in my collection taken 
at Upton, Me., July 27, 1874. 
