SPINE-TAILED SWIFT. 
largest of the Gypselines yet discovered, is a summer visitant of the eastern 
portions of Australia, proceeding as far south as Tasmania ; but its visits to 
this island are not so regular as to New South Wales. During the months 
of January and February it appears in large flocks, which, after spending a 
few days, disappear as suddenly as they arrived. I am not aware of its having 
been observed in Western Australia, neither has it occurred in any of the 
collections formed at Port Essington, although it doubtless pays that colony 
passing visits during its migrations. I believe it will be found that Indian 
and Australian examples do not differ. It is supposed to have been known 
to Pallas ; and if so, it is the bird described by that author as Hirundo ciris. 
Von Schrenck found it in Amoorland, and it is also said to have once occurred 
in England. Mr. Jerdon states that it breeds among the huge wall-like crags 
of the Himalayas, and under the snow-level. The keel or breastbone of this 
species is more than ordinarily deep, and the pectoral muscles more developed 
than in any bird of its weight with which I am acquainted. Its whole form 
is especially and beautifully adapted for extended flights ; hence it readily 
passes from one part of the world to another, and, if so disposed, may be 
engaged in hawking for flies on the continent of Australia at one hour, and 
in the next be similarly employed in Tasmania. So exclusively is this bird 
a tenant of the air, that I never, in any instance, saw it perch, and but rarely 
sufficiently near the earth to admit of a successful shot ; it is only late in the 
evening and during lov^ery weather that such an object can be accomplished. 
With the exception of the Crane, it is certainly the most lofty as well as the 
most vigorous flier of the Australian birds. I have frequently observed in 
the middle of the hottest days, while tying prostrate on the ground mth my 
eyes directed upwards, the cloudless blue sky peopled at an immense 
elevation by hundreds of these birds, performing extensive curves and 
sweeping flights, doubtless attracted thither by the insects that soar aloft 
during serene weatiier ; on the contrary, the flocks that visit the more humid 
chmate of Tasmania necessarily seek their food near the earth.” 
Miss Cheney recorded in the Emu, Vol. XIV., p. 207, 1915, for the 
Wangaratta District, Victoria : “ In 1914 these birds remained until the end 
of April. Usually we did not see them after February. I think there mhst 
have been an unusual number of insects to keep them, they were skimming 
so close to the ground. Two or three were seen on the 5th November last, 
but the main flight did not come until December.” 
Mr. J. W. Mellor wrote me : “I have seen these large Swifts common in 
Tasmania, where they fly about in mid-air, capturing their insect food on the 
wing, never seeming to tire, as they are not seen to settle to rest from morning 
till night.” 
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