dome, only one is needed at the moment; but the Bee rightly calculates
that the others will be useful presently for the other eggs; and she
watches them all with jealous vigilance to drive away possible
visitors. Indeed I do not remember ever seeing two Masons working on
the same pebble.

The task is now very simple. The Bee examines the old cell to see what
parts require repairing. She tears off the strips of cocoon hanging
from the walls, removes the fragments of clay that fell from the
ceiling when pierced by the last inhabitant to make her exit, gives a
coat of mortar to the dilapidated parts, mends the opening a little;
and that is all. Next come the storing, the laying of the eggs and the
closing of the chamber. When all the cells, one after the other, are
thus furnished, the outer cover, the mortar dome, receives a few
repairs if it needs them; and the thing is done.

The Sicilian Mason-bee prefers company to a solitary life and
establishes herself in her hundreds, very often in many thousands,
under the tiles of a shed or the edge of a roof. These do not
constitute a true society, with common interests to which all attend,
but a mere gathering, where each works for herself and is not
concerned with the rest, in short, a throng of workers recalling the
swarm of a hive only by their numbers and their eagerness. The mortar
employed is the same as that of the Mason-bee of the Walls, equally
unyielding and waterproof, but thinner and without pebbles. The old
nests are used first. Every free chamber is repaired, stocked and
sealed up. But the old cells are far from sufficient for the
population, which increases rapidly from year to year. Then, on the
surface of the nest, whose chambers are hidden under the old general
mortar covering, new cells are built, as the needs of the laying-time