76 BIRDS OF TASMANIA. 



in general; also Mongolia, Baikal, Amoor, Cachar, Burmah, Assam, 

 Japan, and China. 



Observations. The records concerning the visits of this Aus- 

 tralian Swift, as it is sometimes called, are but few. The reason 

 is not far to seek, for it is usually in company with the Spine- 

 tailed species, whose powers of flight are well known. It is almost 

 if not quite a matter of impossibility to distinguish one species from 

 another, unless they are flying low and passing and repassing in 

 front of the observer. The first record I made of the White-rumped 

 Swift was during the autumn of 1902, when a number were seen 

 in company with a large flock of Spine-tails, the whole flying low 

 down. This was late one afternoon. In February, 1896, Colonel 

 Legge observed several examples among a large flock of Swifts 

 " dashing " about the homestead at Cullenswood. 



Sub- Family Chaeturinae. 

 *SPINE-TAILED SWIFT 

 (Chcetura caudacuta, Lath.) 



Male. Forehead generally wholly white; crown, nape, and 

 sides of the head blackish-brown, with metallic gloss ; back, 

 shoulders, and rump pale brown, lightest in centre of back ; wings 

 and tail black, glossed with greenish and steel blue; inner webs 

 of innermost secondaries mostly white ; chin, throat, and under 

 tail coverts white ; rest of under surface sooty-brown ; lower flanks 

 glossy bluish-black, with white tips ; bill blackish ; legs and feet 

 blackish-brown. Dimensions in mm.:- Length, 200-202; bill, 

 7.75-78; wing, 195-210; tail, 51-57; tarsus, 14.5-15. It will be 

 noted from the above measurements that individuals vary some- 

 what considerably in certain parts. 



Female. Similar to male. 



Young. Practically no white on forehead; brownish spots on 

 under tail coverts. 



Nest. Mr. D. Le Souef (Emu, vol. vii., p. 73) describes the 

 nest, as seen by him under the Kegan Waterfall, in Japan, as 

 being large and made of mud, evidently of two or three colours, 

 and built on a sloping wall of rock well under cover. ' ' The nest 

 is about a foot in depth externally by about 4 inches across on the 

 top; the cup or egg cavity was evidently shallow, as the sitting 

 bird was well exposed." 



Eggs. So far as I am aware, they are still undescribed. 



Breeding Season. (?). 



Geographical Distribution. Tasmania and Australia; also Mon- 

 golia, Eastern Siberia, China, and Japan. 



Observations. This projectile of a bird usually first appears in 

 Tasmania about the second week in February, and the last one 

 for the season about the end of March. I have records, however, 



