In the open fields as in the confinement of my cages, the burrow is always dug under the heap of dung that is being exploited. No outward sign betrays its presence, concealed as it is beneath the voluminous droppings of the Mule. It is a cylindrical passage, the same width as the neck of a claret-bottle, straight and perpendicular in a homogeneous soil, bent and winding irregularly in rough ground where a root or stone may bar the way and necessitate an abrupt change of direction. In my cages, when the layer of earth is insufficient, the pit, at first vertical, bends at right angles on touching the wooden floor and is continued horizontally. There is no precise rule therefore in the boring. The accidents of the soil determine the shape. At the end of the gallery again there is nothing to remind us of the spacious hall, the workshop where Copres, Scarabæi and Gymnopleuri fashion their artistic pears and ovoids, but a mere cul-de-sac of the same diameter as the nest. A veritable drill-hole, if we make allowances for the occasional knots and twists inevitable in boring through stuff that offers more resistance at some places than at others; a winding channel: that is what the Geotrupes’ burrow is. The contents of the crude dwelling take the form of a sort of sausage or pudding, which fills the lower part of the cylinder and fits it exactly. Its length is not far short of eight inches and its width about an inch and a half, when the thing belongs to the Stercoraceous Geotrupes. The dimensions are a little smaller in the work of the Mimic Geotrupes. In either case, the sausage is nearly always irregular in shape, now curved, now more or less dented. These imperfections of the surface are due to the accidents of a stony ground, which the insect does not always excavate according to the canons of its art, which favours the straight line and the perpendicular. The moulded material faithfully reproduces all the irregularities of its mould. The lower end is rounded off like the bottom of the burrow itself; the upper end is slightly concave, through being packed more closely in the middle.