Within lies one head of game—one only—quite small and quite insufficient for the voracious nursling for whom it is destined. It is a golden green-fly, Lucilia Cæsar, a dweller in tainted meat, and is quite motionless. Is it really dead or only paralysed? This will be cleared up later. Just now let us observe the cylindrical egg upon its side, white, slightly curved, and a couple of millimetres in length. It is a Bembex egg. As we have foreseen from the mother’s behaviour, there is no pressing household business; the egg is laid and a first ration provided for the needs of the feeble larva, which ought to hatch in twenty-four hours. For some time the Bembex need not re-enter her hole, confining herself to keeping a good lookout in the neighbourhood, or possibly making new burrows and laying there egg after egg, always in a separate cell. This peculiarity of beginning to lay in food by a single small piece of game is not peculiar to Bembex rostrata; all the other species do the same. Open any cell after the egg is laid, and you always find it glued to the side of a Dipteron—all the food there is; moreover, this first ration is invariably small, as if the mother had sought some specially tender mouthful for her frail nursling. Another motive, the freshness of the food, may also have guided her choice. Later we will look further into the matter. This first ration—always a moderate one—varies much, according to the frequency of such or such a kind of game in the neighbourhood. It is sometimes a Lucilia Cæsar, sometimes a Stomoxys, or some small Eristalis, or a delicate Bombylius clad in black velvet, but the commonest is a Sphærophoria with a slender abdomen. This fact (and it has no exception) of storing the nest with but a single Dipteron,—a ration far too meagre for a larva with a voracious appetite,—at once puts us on the track of the most remarkable habit of the Bembecidæ. Hymenoptera whose larvæ live on prey heap into each cell the whole number of victims needed by the grub, which is hatched and lives alone,—an egg having been laid on one fly and the dwelling closed up. The larva has before it its whole store of food. But the Bembex is an exception to this rule. First a head of game is brought to the cell and an egg dropped on it. Then the mother leaves the burrow, which closes of its own accord; besides which she takes care to rake the surface smooth, and hide the entrance from every eye but her own.