aware. The larvæ must vary very much in their tastes; one can imagine that a nice juicy caterpillar, or even a good fat grasshopper, may be appetizing and easily assimilated, but one can equally fancy that the larvæ, who wake up to find their food consisting of small hard beetles, may feel more or less resentment against their parents' ideas of dainties for the young! Still they seem to thrive on it, and come out eventually as exact likenesses of their parents. A large number of the fossors inhabit dry sandy wastes, such as the dunes along the sea coast at Deal, Lowestoft,

etc.; many of these, when they leave their burrows, throw up some sand over the hole so as completely to cover it; how these insects find the spot again after a lengthy chase after spiders or other prey is a marvel; and yet those who have observed carefully say that they come home from long distances with unerring precision. No sense of which we have any knowledge, however accentuated, seems to explain this. To be able to arrive back at a home in an extensive arid sandy plain, where no outward sign indicates its whereabouts, must surely require perception of a different nature from any of those with which we are endowed. Some fossors are subject to the depredations of cuckoos, just as the solitary bees are, but their cuckoos are rarely of aculeate origin. The only ones which I have had any opportunity of studying are the species which nest in bramble stems. The cuckoos which associate with them are some of the smaller jewel flies and Ichneumons: the habits of both these differ from those of the aculeate cuckoos, the jewel flies devouring the larva of the aculeate and the Ichneumon laying its eggs in it. The fossors

Fig. 2. vary exceedingly in size, shape and colour. Our largest species are about an inch long and our smallest about the eighth of an inch, nearly all having the body where it joins the thorax constricted into a very narrow waist; this is sometimes of considerable length. In one genus known to entomologists by the name Ammophila (fig. 2) or "lover of the sand", the waist is practically the longest part of the body, so that looking at one sideways as it flies along, one could almost be deceived into thinking that there were two insects, one following the other (cf. pl. A, fig. 7). In colour, there seem to be three dominant schemes: Black (cf. pl. B, fig. 17); black with a red band across the body (cf. pl. A, fig. 7); and black banded with yellow, like a wasp (cf. pl. A, figs. 6 and 8, etc.) In some the yellow bands may not be complete, and appear only as spots on each side of the body segments, or the red band may be almost obliterated, or the black species may

Fig. 3. Fig. 4. be more or less variegated with yellow spots on the head and thorax, but as a general rule all our species fall into one or other of these colour schemes. The females of some of our sand frequenting species have beautiful combs on their front feet, each joint of the tarsi having one or more long spines on its external side (figs. 3 and 4). These are of importance to them in their burrowing, as they enable them to move with one kick of their front leg a considerable amount of the dry sand in which they make their nests. Although sandy commons, etc., are the resort of many fossors, others may be found burrowing in wood or in hard pathways or banks; in fact, like most other insects, some of their members may be found almost anywhere.

THE SOLITARY WASPS

The ordinary wasps are acquaintances of every one, but the solitary or keyhole wasps are not so well known, although they are far from uncommon. They are little narrow black insects striped across the body with yellow, belonging to the genus Odynerus (pl. A, 9), and might hardly be recognized as belonging to the same family as the true or social wasps. Still they have considerable powers of stinging, and fold their wings lengthwise when at rest like their larger relatives. I dare say some people may have noticed that a wasp's wing sometimes assumes a narrow straight form, quite unlike what it is when expanded. This is due to the wasp being able to fold its wing lengthwise like a fan. The wasp tribe are, so far as I know, the only stinging Hymenoptera which have this power.