mine the
masses of boulders, at no great height from the ground, where the
fierce rays have heated them to the temperature of a Turkish bath; and,
perhaps, if you seek long enough, you will light upon the structure of
Eumenes Amedei. The insect is scarce and lives apart; a meeting is an
event upon which we must not count with too great confidence. It is an
African species and loves the heat that ripens the carob and the date.
It haunts the sunniest spots and selects rocks or firm stones as a
foundation for its nest. Sometimes also, but seldom, it copies the
Chalicodoma of the Walls and builds upon an ordinary pebble. (Or
Mason-bee.--Translator's Note.)

Eumenes pomiformis is much more common and is comparatively indifferent
to the nature of the foundation whereon she erects her cells. She
builds on walls, on isolated stones, on the wood of the inner surface
of half-closed shutters; or else she adopts an aerial base, the slender
twig of a shrub, the withered sprig of a plant of some sort. Any form
of support serves her purpose. Nor does she trouble about shelter. Less
chilly than her African cousin, she does not shun the unprotected
spaces exposed to every wind that blows.

When erected on a horizontal surface, where nothing interferes with it,
the structure of Eumenes Amedei is a symmetrical cupola, a spherical
skull-cap, with, at the top, a narrow passage just wide enough for the
insect, and surmounted by a neatly funnelled neck. It suggests the
round hut of the Eskimo or of the ancient Gael, with its central
chimney. Two centimetres and a half (.97 inch.--Translator's Note.),
more or less, represent the diameter, and two centimetres the height.
(.78 inch.--Translator's Note.) When the support is a perpendicular
plane, the building still retains the domed shape, but the entrance-
and exit-funnel opens at the side, upwards. The floor of this apartment
calls for no labour: it is supplied direct by the bare stone.

Having chosen the site, the builder erects a circular fence about three
millimetres thick. (.118 inch.--Translator's Note.) The materials
consist of mortar and small stones. The insect selects its stone-quarry
in some well-trodden path, on some neighbouring road, at the driest,
hardest spots. With its mandibles, it scrapes together a small quantity
of dust and saturates it with saliva until the whole becomes a regular
hydraulic mortar which soon sets and is no longer susceptible to water.
The Mason-bees have