in the hornet. Here, as in the abdomen, we may notice varieties of colour, depending merely on individual or sexual peculiarities and not constituting specific differences. The large convex surface which forms the middle of the thorax has its dark brown relieved by a broad tongue of a lighter colour, corresponding to the position of the great longitudinal muscles of the thorax. This gets narrower as it passes backwards, and is divided down the centre by a dark streak of a thin wedge shape. The different colours are most distinctly shown in the male insect.

In the abdomen, it might appear as if the markings were reducible to two types. But as these distinctions of colour are not connected with any of the variations of size so remarkable in the hornet, nor with any fixed habit of building, nor with any peculiarity of structure whatever, they may be regarded as unimportant, or at least as insufficient to build the distinction of a species on. There is but one British hornet. In this, as in the smaller species, the chief characters are borne on the first and second abdominal rings. The first is marked by a broad band of dark brown, fading gradually as it approaches the edge of the scale, where it abruptly ceases, and a bright yellow line runs along the border. In the lighter coloured specimens secondary lines may be traced within this broad band, and the truncated end of the abdomen has cloudy markings which are lost in the darker insects. In the second ring we have a similar alternation of zones of different shades, shown most distinctly in the lightest coloured specimens. A dark zone sends out a rounded point from beneath the preceding ring, then follows a broad paler band, deepening towards the edge, till

it suddenly changes, as before, into a broad yellow border. The smooth edge observed in the first segment is broken in the second by three projections or cusps; one larger, central, paler; and two smaller, lateral, more defined, and of a deeper colour. These diminish regularly on each successive ring; the central most rapidly. After the third ring the point of the central cusp has generally disappeared, but the square or clubbed ends of the lateral cusps still project from beneath the edge of each preceding scale to the last.

The markings of the perfect and imperfect female, that is of the queen and the worker, are nearly identical, only a little more decided perhaps, as might have been expected, in the perfect insect. The central cusp in the worker is rather more pointed and proportionally longer. In the male-the drone—the central cusp is much less prominent, and is rounded rather than pointed. And the specific characters scarcely come out till the third segment, instead of appearing, as in the females, on the second.

The six species of smaller wasps are all nearly of the same size, except V. vulgaris, the workers of which are generally rather below the average dimensions of the others. And they are all nearly of the same colour, except V. britannica and V. rufa, which have certain patches of an orange hue mixed with the regulation black and yellow uniform. The distinctive markings are to be looked for on the clypeus and the two first abdominal rings, as in the hornet. But, besides these, a most important distinction is to be found in the colour of the scape, the long first joint,

of the antennæ, by which they may be divided into two classes. In all the sexes of all three species of tree-wasp the scape is yellow in front. In the ground-wasps the antennæ of the females and workers are black all over, only the males having yellow scapes. We must not say at once that because a wasp has a yellow scape she never builds in the ground, for V. sylvestris seems to build above or underground indifferently, nothwithstanding her yellow scape. And other exceptions are constantly occurring. But still, as a general rule, the colour of the scape in the female Vespa indicates their habits in this particular very exactly.

V. britannica, Plate II, one of the tree-wasps, is generally easily recognized by her dark appearance, but she has besides some very well marked distinctive characters. The face is very dark, the bounding yellow line of the compound eyes being almost too fine to be seen, and the only relief being given by the scapes, the small corona, and a comparatively small portion of the clypeus. This last is divided from top to bottom by a broad black line, swelling out on either side into something of the figure of a spear-head pointing downwards, the angles being more or less acute in different specimens. The corona is small, and is divided into two lobes by a deep notch both above and below. Alone, of all the species, the face of this wasp is quite unmistakeable.

Turning to the dorsal aspect of the insect, we find on the vertex of the head and on the thorax but few distinctive marks. For the two yellow spots which appear on the metathorax, one on either side, are

common to the other tree-wasps as well as to V. rufa also. Again, the yellow lines which converge from the root of the wings on either side to the back of the head, the yellow triangular spots beneath the wings, and the yellow line visible on this aspect behind the upper limb of the compound eyes are common to all the species. They are of use in distinguishing these Vespa from others, but between one British species and another they have no significance.

The truncated end of the abdomen is black, and a band of this colour is extended a little beyond the square edge where the dorsal aspect begins. In the middle this black marking comes down in an obtuse angle. At the sides it slopes off in an even line, except where it is encroached upon by an orangecoloured spot. The yellow border of this ring has also a very decided orange tint. The second ring, in the same way, presents a bluntish cusp in the centre, but, instead of narrowing from this point, the black band sweeps down, in a saddle shape, to the two lateral cusps, which are square, not pointed, at the end. Then it suddenly turns up, and in the notch thus made a bright orange spot is generally to be seen. The central cusp disappears in the succeeding rings; and, as the band becomes narrower, the ends of the lateral ones are disconnected with it and stand out as isolated black spots on the yellow ground.

The male has the same markings on the face and thorax as the female. But the orange spot on the second abdominal ring is more decided in this sex. The black bands are of a more uniform width, and their outline is less broken by the projecting cusps. Sometimes the female of this species is covered with

long black hair, so as to present quite a rough furry appearance.

V. sylvestris, Plate II, is a larger insect than the preceding, and of a lighter colour; she stands higher, and is altogether the most beautiful of the British social wasps. Commencing, as before, with the female: her clypeus is marked with a single dark spot in the centre. A fine yellow line runs round the inner edge of the compound eyes, and the corona is a more prominent feature than in V. britannica. This is larger; its upper edge is slightly hollowed out in the middle; two little notches are seen on each side; and the outline of the lower edge is broken in the centre by a round hole being gouged out as it were. These figures need a lens to trace them, but they give very important differential characters.

The thorax resembles that of V. britannica, and so, but for the absence of the orange tint, does the first abdominal ring. The second ring is more distinctive. There is a broad black band, gradually narrowing from the central point, the regular sweep of which is but little interfered with by the slight projection of the angular lateral cusps. And these slight projections rapidly disappear in the succeeding rings. The male differs from the female in the more uniform width of the black bands on the abdominal rings; they contract less from the central point, though their sweep is more broken by projecting lateral cusps. These are most distinct in the worker. The central point on the first ring is more prominent in the male

insect.