144 GARDEN AND AVIARY BIRDS. 
with the tail rather longer and slightly forked (Cypselus 
subfurcatus). It is sociable in habits, and builds in num- 
bers in houses, making nests of any sort of light rubbish 
it can pick up on the wing, such as feathers, straw, etc. 
The materials are stuck together with saliva, and the nest 
varies in shape, and may be either in a hole or stuck to 
the roof. 
Three eggs are usually laid, and two broods brought 
off in a year, the breeding-season lasting from February 
to August, and the birds resorting constantly to the same 
nest, which they also use for sleeping and resting, never 
perching outside. It has been said that these birds can- 
not rise from the ground, but this is a mistake ; at least, 
in several experiments, I found only one uninjured bird 
that could not; birds that are obviously hurt are fre- 
quently found, for this Swift is constantly getting into 
difficulties by entering places whence it cannot readily 
escape ; it seems to be a very stupid bird. 
It has a clear shrill squeal, most frequently uttered 
before roosting time, when flocks of them career round 
and round before going to bed. It is not a migratory 
species, and in places where it is common, as at Calcutta, 
is one of the most conspicuous birds at all times. I doubt 
if it is advisable to encourage these bird: where Swallows 
can be got to build, as they are not nearly so attractive as 
the latter, and are apt to drive them away in order to take 
their nests. But in default of the real Swallows, Swifts 
are better than nothing. 
Tue Patm-Swirt (Tachornis batassiensis) is only /a 
little less in length than the House-Swift, but is really a 
