‘Everything is good that harmonizes with the functions to be fulfilled. The grub requires a cement-bag to safeguard its provisions against desiccation; it is born with a knapsack on its back so that it may live.’ Thus is the hump excused and abundantly justified. Its usefulness is displayed from another point of view. The thimble is of such a niggardly size that the grub consumes it almost entirely. All that remains is a thin layer, a crumbling remnant which would provide no security for the nymph. The ruined dwelling has to be strengthened, to be lined with a new wall. For this purpose, the larva of the Oniticellus empties the whole of its knapsack and gives its cell a complete coating of cement, after the manner of the Sacred Beetle and others. The grub of the different species of Onthophagi does more artistic work. Placing its putty drop by drop, it constructs a mosaic of lightly-projecting scales, suggesting those of a cedar-cone. When finished, well dried and stripped of the last shreds of the original thimble, the shell thus obtained by the Bull Onthophagus is the size of an average filbert and resembles the pretty cone of the alder-tree. The imitation is so good that I was taken in by it the first time that I handled the curious product when digging in my cages. It needed the contents of the mock alder-cone to show me my mistake. The hump has an artfulness of its own: it was keeping this elegant specimen of stercoral jewellery in reserve for us. The nymph of the Onthophagi provides us with another surprise. My observations are confined to two species only: the Bull Onthophagus and the Forked Onthophagus; but the difference between the two, in size and shape, is great enough to allow me to generalize and apply the following singular fact to the whole genus. About the middle of the fore-edge of the corselet the nymph is armed with a very distinct horn, projecting for about one-twelfth of an inch. The horn is transparent, colourless and limp, as are all the budding organs at this period, particularly the legs, the cornicles of the forehead and the mouth-parts. This crystalline protuberance proclaims a future horn as clearly as the mandible is proclaimed by its initial nipple or the wing-case by its sheath. Any insect-collector will understand my amazement. A horn there, on the prothorax! But no Onthophagus wears such a weapon as that! The register of my insect-house duly records the genus of the insect, but I dare not believe it. The nymph moults. Together with the cast skin, the unfamiliar horn dries up and falls off, leaving not the least trace behind it. My two Onthophagi, recently disguised in strange armour, now have their corselets bare.