We will return, therefore, to the Sphex-wasps working on level ground, in ordinary soil, as happens in by far the greater number of cases. As soon as the burrow is dug, the chase begins. Let us profit by the Wasp’s distant excursions in search of her game and examine the dwelling. The usual site of a Sphex colony is, as I said, level ground. Nevertheless, the soil is not so smooth but that we find a few little mounds crowned with a tuft of grass or wormwood, a few cracks consolidated by the scanty roots of the vegetation that covers them. It is in the sides of these furrows that the Sphex builds her dwelling. The gallery consists first of a horizontal portion, two or three inches long and serving as an approach to the hidden retreat destined for the provisions and the larvæ. It is in this entrance-passage that the Sphex takes shelter in bad weather; it is here that she retires for the night and rests for a few moments in the daytime, putting outside only her expressive face, with its great, bold eyes. Following on the vestibule comes a sudden bend, which descends more or less obliquely to a depth of two or three inches more and ends in an oval cell of somewhat larger diameter, whose main axis lies horizontally. The walls of the cell are not coated with any particular cement; but, in spite of their bareness, we can see that they have been the object of the most conscientious labour. The sand has been heaped up and carefully levelled on the floor, the ceiling and the sides, so as to prevent landslips and remove any roughness that might hurt the delicate skin of the grub. Lastly, this cell communicates with the passage by a narrow entrance, just wide enough to admit the Sphex laden with her prey.