Wood Swallows 723 



manner of a swarm of bees. In cold or wet weather they select a spot under an 

 overhanging flake of bark, under a leaning tree, or in the branches of a tree near 

 the ground or well up, where they cluster one upon another, with the heads all 

 upward, sometimes forming bunches "two armfuls around." The object of 

 this is unknown unless it is for mutual warmth and protection, as it has only 

 been observed on wet or cold days. When a cluster is suddenly disturbed from 

 this position the rustle of the myriad wings as they are startled into flight has been 

 likened to a mild clap of thunder. On the ground beneath a cluster it is not 

 unusual to find several dead birds which have been smothered or have succumbed 

 to the cold. 



The Wood Swallows number about twenty species, and all but one are re- 

 ferred to the genus Artamus, this being the West African False Swallow (Pseu- 

 dochelidon). They appear to have their center of distribution in Australia, but 

 occur as well in New Guinea, Moluccas, Celebes, Philippines, Borneo, Java, etc. 

 The head, throat, and back are sooty gray, the primaries and tail brownish black, 

 and the rump, chest, and under parts mostly pure white. They frequent the 

 vicinity of water and build an open nest of coarse yellowish grass, in Australia, 

 usually placing it within the old abandoned nest of the Magpie Lark (Grallina 

 picata) occasionally in a hollow limb or rarely in a forking branch. The eggs, 

 usually four in number, are pointed oval in shape and pinkish white, blotched 

 chiefly around the larger end with brown. The nesting season extends from Sep- 

 tember to January, and usually two broods are reared in a season. A very hand- 

 some species, inhabiting mainly the great interior of Australia, is the White-browed 

 Wood Swallow (A. superciliosus\ a bird about seven inches long, with the 

 upper parts dark gray and the lower parts a deep rich chestnut, while the head 

 is mainly black set off by a stripe of pure white over the eye, whence of course the 

 common name. The female is similar but paler. They usually construct an 

 independent nest, placing it in a forked branch or on a bit of projecting bark, 

 though occasionally making use of an abandoned nest; the eggs are two or three 

 in number and greenish gray mottled and spotted with umber and slate. In 

 seasons of protracted drought or on the occasion of a caterpillar or locust plague, 

 they often move in flocks toward the seacoast ; their destruction of these noxious 

 insects is immense. Another species is the Masked Wood Swallow (A. persona- 

 tus\ so called from the fact that the face, ear-coverts, and throat are jet-black, 

 the remainder of the plumage both above and below being gray. Their habits 

 are similar to those of the last except that they appear to line their nests with 

 green instead of dead grass. Other species are the Dusky Wood Swallow (A. 

 sordidus\ w r hich is dusky gray throughout except the dark bluish black wings, 

 the outer primaries of which are edged with white, and the Little Wood Swallow 

 (A. minor], which is the smallest of the group, being only about five and a half 

 inches long and resembling the last-mentioned in miniature. Of the Indian 

 species (A. fuscus), Oates says: " They are usually found in flocks. They perch 

 chiefly on dead trees and launch themselves into the air to capture insects, 

 returning to the same perch again; at times, however, the whole flock will sail 

 about high in the air for long intervals, after the manner of the Swallows but 



