12 
EEAUTirUL BIRDS. 
tlie common fern lines the \Yhole. The base of the 
nest is continued round the stem of the branch, to 
which it closely adheres, and, when viewed from 
below, appears a mere mossy knot or accidental pro- 
tuberance. 
Lesson has described the nest of one species as 
principally composed of a spongy, cellular substance, 
-apparently similar to that of a fungus, of which some 
species of wasps build large habitations, suspended 
from the branches of trees in the virgin forests of 
Griiiana, and the same naturalist gives a figure of the 
nest of another species, composed entirely of the down 
of some thistle ; the seed is attached, and is placed 
outwards, giving a jagged or prickly appearance to 
the outside, ivhile tlie interior is warmly lined with 
the down. Two eggs only are laid by these birds. 
The period of incubation is remarkahl}^ short. La- 
tham says that the black Humming Bird sits twelve 
da vs, and that tlie vouno: leave the nest and follow 
their parents in eighteen days ; and the 2s orth 
American species, according to Audubon, hatches only 
ten days, and the young are ready to fly in one week. 
Those species which have the hill perfectly straight, 
and the tail ever so slightly divaricated, are considered 
the typical species. In the receding groups on either 
side, the hill is more or less curved, 'sometimes de- 
pressed at the base, and the tail is forked or rounded ; 
in some species, the external feathers of the tail are 
considerably produced , in others, again, the two 
middle tail feathers are much longer than any of the 
rest. 
The species which we have figured are the recinwed 
