284 Passeres. BIRDS. Cypselid.®. 
clinging like squirrels means of tlieir strong feet and 
sharp claws. The young birds are indeed so conscious 
of the power of their feet, that it is not uncommon for 
them to quit the nest voluntarily long before they can 
fly ; they then cling firmly to the wall, and are fed there 
until they can dart oft' in pursuit of their own prey. 
Wilson says that “ the Chimney Swallow is easily 
distinguished in the air from the rest of its tribe, by its 
long wings, its short body, the quick and slight vibra- 
tions of its wings, and its wide unexpected diving 
rapidity of flight ; shooting swiftly in various directions 
without any apparent motion of the wings, and uttering 
the sounds (sip (sip (sip (see (see in a hurried manner. 
In roosting, the thorny extremities of its tail are thrown 
in for its support. It is never seen to alight but in 
hollow trees or chimneys ; it is always most gay and 
active in wet and gloomy weather ; and is the earliest 
abroad in the morning, and latest out in the evening of 
all our swallows.” 
THE NEEDLE-TAILED SWIFT {AcanthyUs cauda- 
cuta) of Australia, is a considerably larger bird than 
the preceding, measuring seven inches in length to the 
extremity of the tail, whilst the wings are of immense 
extent, measuring no less than nine itiches from the 
wrist-joint to the tip, and thus extending at least three 
times the length of the bird. Its general colour is 
brown ; the wings, tail, and crown of the head, are 
deep, shining green ; the throat and chin, a band above 
the bill, the inner webs of the innermost secondaries, 
and the hinder part of the abdomen, with the lower tail 
coverts, are pure white. It is an abundant summer 
bird in New South Wales and Van Diemen’s Land, 
and its rapidity of flight, as might be expected from 
the great length of its wings, is so extraordinary, that 
as Mr. Gould remarks, it might be engaged in hawking 
for flies on the continent of Australia and on the island 
of Van Diemen’s Land within half an hour. It flies 
in large flocks at a great height in the air, at least on 
the Australian continent, where the clear dry air causes 
the insects to rise to a great elevation ; in Van Die- 
men’s Land, on the contrary, where the air is moist, 
and the insects fly low, this Swift also skims along not 
far from the surface of the ground. The nidification of 
this bird is not known. 
THE SHARP-TAILED SWIFT {AcanthyUs .oxyurd) is 
an inhabitant of South America, especially of Paraguay, 
where, according to D’Azara, it is called by the Indians 
M biyuirnhopi, or the Bat-Svmllow, from a resemblance, 
both of its colour and mode of flight, to those of a 
bat. It flies principally above the highest trees of 
the woods of Paraguay, and when it passes to the 
open country rarely descends within thirty or forty 
feet of the earth, even then rising again speedily to its 
ordinary elevated position. It is a very shy biixl. 
Like all the Swifts it drinks on the wing, flying rapidly 
over the surface of the water, and taking up a little sip 
in passing. It passes with great rapidity, but with the 
utmost precision, amongst the branches of trees, and 
when thus engaged often carries off spiders from the 
webs which they have spread there ; and it is in the 
cavity of a hollow tree that it passes the night. In 
flying this bird produces a sound which is compared by 
D’Azara to that of a very small pair of castanets. 
THE HOODED SWIFT {Dendrochclidon comatus). 
The genus, to which the name of Dendrochelidon, or 
Tree-swallow, has been applied, consists entirely of 
eastern species, peculiar to India and the islands of the 
Indian Archipelago. They have the hinder toe non- 
versatile, the tail forked, and the head usually adorned 
with an erectile crest or with tufts of feathers. The 
Hooded Swift, which is an inhabitant of the numerous 
islands of the Eastern Sea, is a beautiful little species, 
measuring only about five inches and a half in length ; 
the general colour of the plumage is a bronze green ; 
but on the head there are some long white feathers, 
which form a sort of hood or crest when erected. The 
belly and under tail-coverts are also white. 
THE BEARDED SWIFT {Dendrochelidon mystaceus), 
which is found only in New Guinea, is another elegant 
species, the contrast of its colours producing a most 
pleasing effect. The colour of the crown of the head, 
of the wings, and tail, is blue-black ; a portion of the 
wing-coverts and the outer web of the external tail 
feathers are white; a white band, originating at the 
nostrils, passes above each eye ; and beneath the lower 
mandible there springs a tuft of small white feathers, 
which borders the gape, and terminates on the sides of 
the neck in two long slender white plumes, exactly 
resembling a wdiite moustache of the true military cut. 
The other parts of the bird are of a brownish slate- 
colour, except the inferior tail-coverts, which are grey. 
THE ESCULENT SWALLOW {Collocalia esculenta)— 
Plate 5, fig. 16 — which we might with more propriety 
call the Esculent Swift, is one of the most remarkable 
birds of the whole tribe of the Fissirostres. This bird, 
with several others belonging to the same genus, is 
found in many parts of India, both on the continent 
and on the islands. Their nests, which are built in 
fissures and caverns of the rocks, are the celebrated 
edible birds’ nests, so highly prized by the Chinese for 
the preparation of soups and sauces. The nests are 
composed almost entirely of the glutinous matter which 
in the other Swifts assists so materially in binding 
together the materials of which the nests are composed, 
and which, as we have previously stated, is secreted by 
the greatly-developed salivary glands. These, in the 
species of the genus Collocalia, or at all events in those 
wdfich are regarded as the piincipal manufacturers of 
the edible nests, are of very laige size. Although this 
view is now generally received, it was long a matter of 
considerable doubt amongst naturalists wdiere and how 
the so-called Esculent Swallows obtained the materials 
of their nests, the most general opinion being that these 
were derived from sea-weeds picked up and eaten or 
masticated by the birds. Hence Thunberg described 
one of the species under the name of Hirundo fuci- 
phaga. There is, however, still considerable doubt as 
to the number of species which make the edible nests. 
According to Linnaeus, his Hirundo escxdenta had white 
spots on all the tail feathers, a character which does 
not occur in any species known to modern naturalists. 
Thunberg describes his Hirundo fuciphaga as being ol 
a black colour; ash colour, dull brown, or white beneath ; 
and with the tail, wings, and feet entirely black. ’iVe 
have placed the name given by Linnaeus at the head 
of this article, as it seems pretty certain that one of the 
