G2) 
as swallows and martins do, so that they must possess marvellous, 
untiring powers of flight. When they return to their nests they 
are neither blown nor tired, but come in as fresh as ever. On 
several occasions I tried to time the speed or velocity they had 
gathered on these homeward flights. Judging from distances the 
eye can follow it must take them, but a few minutes to traverse 
the distance between Darjeeling and their nests, which took me 
nearly a week to get there. They appear to make a well calculated 
bee-line, occasionally they over shoot the mark by a foot or two, 
how each swift remembers the exact position of its nest is no easy 
matter to explain. Swifts differ much from swallows and martins, 
chief of these we might say is their feet, also in the construction of 
their nests, which are made either of pure glutine from the large 
salivary glands or mixed with paper, pulp, rags ete : Their feet are 
composed of two phalanges and can be directed all the toes forward, an 
admirable aid to clinging to a perpendicular ledges or tiers of rocks ; 
their wings are strong and muscular ; the thorax bone reveals their 
superiority of flight over the swallows and martins. Bill is small 
and hooked ; wings very long ard pointed ; tail short; feet short ; 
hind toe reversible directed forward (when necessary). 
(95) ACANTHYLIS SyLvatica, /White-Rumped Spine-tail, belongs 
to a typical group amongst the swifts. The tail feathers are rigid, 
ending with sharp needle-like spines. These birds are seldom seen in 
Darjeeling, they are more frequently met with from 4000 to 5000 ft. 
elevation. Tail is short and has a wedge-like appearance. Sylvatica 
is 44 inches long. It has the sombre look of the martins, with long 
pointed swift’s wings ; above, the plumage is black with a glossy 
greenish tinge ; white on the rump and upper tail coverts as the 
name implies ; breast and throat grey ; under parts of the body 
white ; bill black. This small swift is usually found hunting over 
scrub jungle and patches of hill cultivation, generally close to running 
streams and springs of water. 
(98° CypseLus Metra, Alpine Swift, represents the group known 
as the true swifts. Birds with long and powerful wings, Ist and 
2nd quills the longest ; tail not infrequently emarginated ; tarsus 
feathered ; toes versatile. Alpine Swift is big in size, being about 
9 inches in length ; wings very long, which reach much beyond, tip of 
the tail, quite 25 inches longer ; wings are 84 inches long ; tail forked 
colour above, is reddish brown, dark on the wings; purple gloss on 
the back ; white on the underparts of the body ; irides brown ; legs 
aud toes purplish in colour. Jelba is not infrequently seen in Dar- 
jeeling. Its flight is strong and vigorous, and has a wide range of 
over a hundred miles, for you will find them at most places in 
Sikkim and the district, after their day’s forage they retire to rest 
at certain localities miles away from their hunting grounds. In 
