268 THE BIKDS OF AUSTRALIA 



Genus CheramoBca. 

 Comprises but one species, which is confined to the Australian 

 Continent. 



The Black and White Swallow. 



CheramoRca leucosternum. 

 Upper surface parti-coloured; crown of head white with brown 

 centres to the feathers, nape and hind neck and sides of neck brown; 

 mantle and upper back white, lower back, rump and tail-coverts and most 

 of the wing blue-black; ear-coverts brown; cheeks, throat, foreneck, and 

 breast, white; abdomen and under tail-coverts blue-black; bill blackish- 

 brown; feet greenish-grey; iris dark reddish-brown. Total length 5.5 inches, 

 culmen .25, wing 8.95, tail 3, tarsus .5. 



The Black and White Swallow is a very wandering species, 

 seen in small flocks of ten to twenty in number. It usually 

 flies very high, more like the Swifts. It more closely resembles 

 the European Sand Martin in its nidification than do any of our 

 other Swallows. It builds sometimes in a deserted burrow of 

 some Bandicoot or Rat Kangaroo, but more generally drills for 

 itself a hole in the side of a bank. The hole is perfectly round, 

 and the passage runs in horizontally for about a yard, and then 

 expands into the nesting chamber. The nest is composed of 

 dry grasses and leaves. Eggs about .67 x .48, pure white, 

 elongated. 



Genus Petrochelidon. 

 Both hemispheres. Martins. 



Head steel-blue with a frontal band of sandy-buff or rufous. 

 P. nigricans. Head all rufous. P. ariel. 



The Tree Martin. 



Petrochelidon nigricans. 



Australia generally and Tasmania, visiting New Zealand, the Papuan 

 Islands and even the Moluccas, migrating north for the winter. 



Above deep steel-blue, lower back and rump whity-brown, upper 

 tail-coverts and tail-feathers dusky-brown: a frontal band of pale brick- 

 red extending backwards to the corner of the eye; lores, feathers round 

 eye, and ear-cuverts sooty-blackish; cheeks and throat dull whitish, with 

 blackish streaks, rest of under-surface whitish with a sandy tinge, a 

 patch of blue-black on the sides of the upper breast. Bill and toes 

 light-brown, iris black. Total length 5.2 inches, culmen .3, wing 4.2, tail 

 2.1, tarsus .5. 



