one point within a radius of twenty rods, over two hundred of these
curious nests, varying in size from that of a small pumpkin to more than
the volume of a barrel. Often a single tree will contain half a dozen
nests or more; and, not unfrequently, the nests of several different
species are seen crowding each other out of shape on the same bush or
tree."

It would be a mistake to think that the widely different nesting habits
I have mentioned are found in different genera. I have just spoken of
the big stick nests, with or without passage-ways, of the Synallaxes,
yet the nest of one member of this group is simply a small straight tube
of woven grass, the aperture only large enough to admit the finger, and
open at both ends, so that the bird can pass in and out without turning
round. Another species scoops a circular hollow in the soil, and builds
over it a dome of fine woven grass. It should be mentioned that the
nesting habits of only about fifteen out of the sixty-five species
comprised in this genus are known to us. In the genus Furnarius the
oven-shaped clay structure is known to be made by three species; a
fourth builds a nest of sticks in a tree; a fifth burrows in the side of
a bank, like a kingfisher.

The explanation of the most striking features of the Dendrocolaptidae,
their monotonous brown plumage, diversity of structure, versatile
habits, and the marvellous development of the nest-making instinct which
they exhibit is to be found, it appears to me, in the fact that they are
the most defenceless of birds. They are timid, unresisting creatures,
without strength or weapons; their movements arc less quick and vigorous
than those of other kinds, and their flight is exceedingly feeble. The
arboreal species flit at intervals from one tree to another; those that
frequent thickets refuse to leave their chosen shelter; while those