324 
LIFE, IN ITS HIGHER FORMS. 
silts) far exceed ours in ingenious adaptation for security 
and defence. Pringle describes them as suspended, twenty 
or more from a single tree, attached to the tips of those 
twigs that hang over a precipice. The body of the nest is 
spherical, and the entrance, which is always from below, is 
through a cylindrical gallery of twelve or fifteen inches in 
length, which projects from the body, exactly like the neck 
of a chemist’s retort. The whole fabric is most ingeniously 
and elegantly woven of a species of very tough grass. The 
object of the precaution displayed in the construction, and 
in the position chosen, is evidently the protection of the 
eggs and young from the baboons and monkeys that would 
othei’wise devour them.* 
We must reluctantly close our enumeration of singular 
nests, with one, whose chief curiosity is the exhibition of 
that social instinct, which, as in the bees, wasps, and ants, 
among Insects, prompts each individual to work on a com- 
mon plan for the general good. The Pensile Grosbeaks, 
just described, associate in their domestic economy, but 
there is no union of labour. Another bird of the same 
family, and of the same country — the Sociable Grosbeak 
( Loxia sneia) of South Africa — builds in concert a huge 
irregular sloping roof of thatch around the stem of a tall 
tree, beneath the eaves of which each pair of birds builds 
its own nest. So numerous are they, however, that the 
nests are in contact with each other, and appeal- to form 
but one structure, distinguished only by the little aperture 
of each. Le Vaillant describes one roof which he examined, 
which contained beneath its eaves three hundred and 
twenty inhabited cells. 
* Ephemerides. 
