"-"1 
FULVOUS OR CLIFF SWALLOW. 67 
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. 
