SWALLOWS 383 



GENUS PROGNE. 



General Characters. Bill long, stout, and convex ; feet large, with 

 strong, curved claws ; tarsus shorter than middle toe and claw ; tail forked 

 for less than half its length. 



KEY TO SPECIES. 



1. Females with under tail coverts streaked subis, p. 3s:-j. 



1'. Females with under tail coverts not streaked . . . hesperia, p. 383. 



611. Progne subis (Linn.). PURPLE MARTIN. 



Adult male. Whole body glossy blue black; wings and tail black; 

 feathers of ventral region entirely sooty grayish beneath the surface. 

 Adult female and immature males with forehead grayish and upper parts 

 sooty glossed with blue black, interrupted by grayish collar ; lower parts 

 grayish in front, whole under parts streaked, the feathers, especially on 

 chest, with distinctly sooty grayish centers. Length : 7.25-8.50, wing 5.65- 

 6.20, tail 3.00-3.40 (forked for .70-.90). 



Distribution. Temperate North America from Ontario and Hudson 

 Bay south to the southern end of Mexican tableland ; wintering in South 

 America. 



Nest. In holes of trees or about buildings and in bird boxes. Eggs : 

 3 to 5, plain white. 



Food. Insects. 



The peculiar vibrant ami at the same time mouthed quality of the 

 martin's song tells of his presence, even when his big steel blue body 

 is not seen floating around overhead. His song, though unpreten- 

 tious, is a talkative twitter very pleasant and companionable. 



But, although we usually associate him with bird boxes and towns, 

 large numbers, especially of the western subspecies, still nest in 

 hollow trees in the mountain forests. 



61 la. P. S. hesperia Brewst. WESTERN MARTIN. 



Adult male. Indistinguishable from male of subis. Adult female : 

 similar to female subis. but light gray of forehead extending back into 

 crown ; feathers of back and rump conspicuously edged with grayish or 

 pale brown ; bend of wing and under coverts mottled profusely with 

 whitish ; anterior under parts and nuchal collar grayish white ; and whole 

 tract from abdomen to under tail coverts almost immaculate white. 



Distribution. Breeds in Pacific coast region from Oregon south through 

 California and Arizona to southern Lower California ; migrates to Nica- 



ragua. 



The examination of birds from British Columbia may show that 

 the}' should be referred to this form. 



GENUS PETROCHELIDON. 



General Characters. Tail short, nearly even ; nostrils without nasal 

 scale, opening directly upward ; tarsus with tuft of feathers above hind 

 toe. 



KEY TO SPECIES. 



1. Forehead white or pale Isabella limifroiis. p. 384. 



1'. Forehead rich chestnut; rarely fawn color . melanogastra, p. 3S4. 



