FULVOUS OR CLIFF SWALLOW. 221 
begins to deposit her eggs, which are four in number, white, 
spotted with dusky brown. ‘The nests are extremely friable, 
and will readily crumble to pieces: they are assembled in 
communities, as represented in the background of our plate. 
In unsettled countries, these birds select a sheltered situation 
under a projecting ledge of rock; and in civilised districts, 
they have already evinced a predilection for the abodes of 
man, by building against the walls of houses, immediately 
under the eaves of the roof, though they have not in the least 
changed their style of architecture. A nest from the latter 
situation is now before me; it is hemispherical, five inches 
wide at its truncated place of attachment to the wall, from 
which it projects six inches, and consists exclusively of a 
mixture of sand and clay, lined on the inside with straw and 
dried grass, negligently disposed for the reception of the eggs. 
The whole external surface is roughened by the projection of 
the various little pellets of earth which compose its substance. 
The entrance is near the top, rounded, projecting, and turning 
downward, so that the nest may be compared to a chemist’s 
retort, flattened on the side applied to the wall, and with the 
principal part of the neck broken off. 
So great is the industry of these interesting little architects, 
that this massive and commodious structure is sometimes 
completed in the course of three days. About the middle of 
July, some nests found near the Rocky Mountains contained 
young ones, while in others the process of incubation had not 
terminated. It is probable that the cliff swallows rear two 
broods in that region, though in Kentucky and Ohio, agree- 
ably to Mr Audubon, they have but one in the year. During 
the first few days of August they assemble in flocks, and, 
after several attempts to commence their migration, they 
finally succeed in obtaining a unanimity of purpose, and they 
disappear as suddenly as they came. 
