FULVOUS OR CLIFF SWALLOW.


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, agreeably 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.


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