Mr. R. Swinhoe on Formosan Ornithology . 253 
The common summer species of China and Japan, C. jotaka, 
Schleg., allied to C. europceus, did not occur in Formosa. 
14. Cypselus vittatus, Jard. & Selb. Ill. Orn. n. s. t. 39. 
This species, which I have noted all along the coast of China, 
from Amoy to Talien Bay, was also seen in S.W. Formosa in 
summer, where, I suspect, a few nidificate, as is the case on many 
islands off the Chinese coast. It is everywhere in China only a 
summer visitant, arriving in early spring. Possessed of very long 
wings, and consequently of extensive powers of flight, it may be 
seen at all hours of the day soaring at a great height, apparently 
never resting till the shades of evening compel it to take refuge 
from the darkness. In damp foggy weather, however, it de¬ 
scends to nearer the earth, darting, with quick flight and screams, 
round hills and other prominences. Like all the species of 
Swifts I have observed, it copulates in the air, the female ar¬ 
resting herself and hovering while the male performs his offices. 
It builds in the holes of houses, often under eaves, and in many 
places in the crevices of rocks. The Cypselus australis, Gould 
(.Hirundo pacifica, Lath.), is a closely related species from Aus¬ 
tralia; but I cannot think it the same, as ours migrates in 
summer in a south-westerly direction, and probably finds winter 
quarters, as is the case with many other species of birds, in the 
plains of Hindostan. It is true that Australia does render us 
one species of Swift, the Chcetura caudacuta (Lath.) (. Hirundo 
ciris, Pallas, Z. R. A. vol. i. p. 541), differing chiefly from its 
Himalayan ally, C. nudipes, Hodgs., in its white forehead; but its 
movements are by no means regular. The Chcetura I never saw 
but once at Amoy, and that was after heavy, stormy weather, when 
a pair were seen, one afternoon, in company with numbers of the 
present species, and one of them was procured. The C. cauda¬ 
cuta , in its wanderings, seems sometimes to range into Amoor- 
land, as noted by Yon Schrenck, and thence even to England; 
but these instances must, I think, at present, until more facts 
are ascertained, be looked upon as certain vagaries that long¬ 
winged birds are guilty of, which t( no fellow can understand,” 
rather than as regular migrations ordained to occur year after 
year. 
