And, first of all, what sites do these builders select for their homes? Should you pass some little garden-wall, facing south, in a sun-scorched corner, look at the stones which are not covered with plaster, look at them one by one, especially the largest; examine 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 search long enough, you will light upon the structure of Eumenes Amadei. 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 [5] and builds upon an ordinary pebble. E. pomiformis is much more common and is comparatively indifferent to the nature of the foundation on which she constructs her cell. She builds on walls, on isolated stones, on the inner wooden 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 E. Amadei is a symmetrical cupola, a spherical skull-cap, having 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. An inch, more or less, represents the diameter; three-quarters of an inch the height. 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.