HIRUNDINID^ — THE SWALLOWS. 335 



of the breast, and a few black feathers in the extreme chin, the latter sometimes scarcely 

 appreciable. Under parts dull white, tinged with reddish-gray on the sides and inside of 

 the wings. Feathers of crissum brownish-gray, edged with whitish, with a tinge of riilbus 

 anteriorly (sometimes almost inappreciable). Nest of mud, lined ; built against rocks or 

 beams ; opening sometimes circular, on the side ; sometimes open above ; eggs spotted. 



Total length, 5.10 ; wing, 4.50 ; tail, 2.40, nearly even ; difference of primary quills, 

 2.10; length of bill from forehead, .38, from nostril, .2-5, along gape, .GO, width, 50; tarsus, 

 .48 ; middle toe and claw, .72 ; claw alone, .22 ; hind toe and claw, .44 ; claw alone, .20. 



Hab. Entire United States from Atlantic to Pacific, and along central i-egion to Arctic 

 Ocean and Fort Yukon ; Panama in winter. Not noted at Cape St. Lucas, in Mexico, or 

 in West Lidies. 



There is no difference between the sexes, but the young bird is very dif- 

 ferent from the adult in the following particulars : the steel-blue above 

 is replaced by a lustreless dusky-brown, the feathers (except on head) 

 being margined with a creamy tint ; the neck merely tinged with rufous ; 

 the throat has only a dusky suffusion, and the chin is much mixed with 

 white ; the frontal patch is obsolete. 



A closely allied species from Mexico, P. sivainsoni (see Baird, Eev. Am. 

 Birds, 1865, 290), possibly yet to be found near our southern border, differs 

 as follows : — 



Frontlet reddish-white, with narrow band of black along upper mandible . lunifrons. 

 Frontlet chestnut-brown, without black at base of upper mandible. Size smaller. 



sivainsoni. 



Sometimes (as in 11,027 $ and 11,025 <?, Fort Bridger) the black patch 

 extends upward, somewhat broken, how^ever, to the bill. 



Habits. The early history of the Cliff Swallow must always remain in- 

 volved in some obscurity, so far as concerns its numbers and distribution 

 before the first settlement of the country, and even do^^•n to the early portion 

 of the present century. Its existence was unknown to J\lr. Wilson, and it 

 was unknown to other naturalists until obtained by Say, in Long's expedi- 

 tion to the Itocky Mountains in 1820. It is now known to occur nearly 

 throughout North America, and to breed from Pennsylvania to the Arctic 

 regions, and from the Atlantic to the Pacific. Yet to many parts of the 

 country it is a new-comer, where, a few years since, it was entirely un- 

 known. It seems to be probable that at first this species was to be found 

 only in certain localities that offered favorable places whereon to construct 

 their nests. Where high limestone cliffs abound, these birds may have 

 always occurred, although escaping observation. 



In the same year that Long discovered this species among the Rocky 

 -Mountains (1820), Sir John Franklin's party also met with it lietween the 

 < 'uniberland House and Fort Enterprise, and on the banks of Point Lake, in 

 latitude 05°. In June, 1825, a number of these birds made their first ap- 

 pearance at Fort Chippewyan, and built their nests under the eaves of the 

 house. This fort had then existed many years, and trading-posts had been 

 in existence a century and a half, and yet this was the first instance of its 



