to the root of the scabbard, where it opens close by the channel in the barbs. The honey-bee's sting has a very similar arrangement, with only one poison gland much longer, however, than the wasp's, and bifurcated at the extremity. Conversely their poison duct is much shorter than that of the wasp. And the bee has less power of withdrawing her sting than the wasp, so that the act of stinging more often proves fatal to these irritable little creatures, which leave both sting and muscular bulb sticking on the hand or glove which has offended them.

The nature of the fluid which, in so minute quantity, causes such excessive pain, is probably not to be determined by chemical analysis, even could we obtain enough of it for this purpose. To litmus-paper it gives a very strong acid reaction, but the pain which follows its introduction into the skin is much greater than a drop of even a highly corrosive acid would cause; and, unfortunately, alkalies are not always a specific cure for its disagreeable effects. The second bite of a snake is said to be less deadly than the first, from the gland having exhausted itself. But as a wasp or bee stings away, for as long as the sting itself lasts, each prick is as sharp as the one before. And judging from the quantity which distils on pressure from the point of the sting there seems to be poison enough to infect all the wounds.

The muscular bulb is a flattened, somewhat oval body, like a seed enveloped in a horny testa. This skin or testa is really a skeleton, corresponding to the outer valves of the male organs, formed of several pieces, and giving attachment to the various muscles which enter into the composition of this delicate and

elaborate piece of mechanism. It is framed in two symmetrical halves, which are united in the middle. line. Between the two segments, in the looser tissue, a passage is found for the poison duct, the oviduct, and the termination of the alimentary canal, arranged in this order. The poison duct lies lowest, just above the scabbard which, besides its other use, serves to bind the two segments of the bulb firmly together along their lower edge. On the upper edge of the bulb, and half encircling it, a kind of saddle is loosely applied. This is the seventh dorsal scale of the abdomen, the twelfth larval segment. Its real nature is obvious, from the spiracles and trachea which we can trace on it. In the male this saddle is not found here, but appears as an external dorsal scale, adding so much to the length of the abdomen in this sex.

Just beneath this diminutive scale lies the end of the alimentary canal, with its vent-cover as already described. The orifice by which the alimentary canal opens externally is almost common to it and to the oviduct, as in birds; the two tubes being separated only by a thin membrane. The edge of this membrane is marked by a tubercle from which a pair of palpi or feelers spring. These are not flexible and jointed like the palpi of the mouth, but straight, and covered on the outer side with fine hairs. When at rest they lie beneath the bulb, parallel to the sting, which lies between and below them, pointing the different way. But, as we press the abdomen and the bulb protrudes, they diverge from the sting and from each other. As the bulb revolves on its axis they point upwards, and the sting, ready to strike, points downwards. Their use may be conjectured, in the absence of direct

observation, from their position and connections. As they are set in motion by the same levers which protrude the sting, it might seem, at first, as if they were connected with its functions. But their employment must rather alternate than coincide with that of the sting; because the action that protrudes the one, withdraws the other organ. They might possibly act as feelers and guides to direct where the sting should be applied; but the sting seems to need no such guidance; and, as the fact, they are not put out as a preliminary to stinging. I believe them rather to be employed in oviposition, to receive the egg from the oviduct and to fix it to the wall of the cell.

Hunter.

Posthumous Works.' Vol. I, p. 80, takes this view of their use. But, on the grounds assigned in the text, I believe it to be

erroneous.

IN the first room of the Northern Zoological Gallery of the British Museum is a beautiful collection of the nests of insects, which has grown up under the care of Mr. F. Smith, during the few last years. Many of these nests have been described and figured in "Homes without Hands." And Mr. Wood's interesting volume affords an excellent introduction to the treasures of this room. It is only with the wasps' nests that we have here to do, but, in this department alone, there is occupation for hours, in the examination of the wonderful contents of the wall-cases.

No insect probably has a more versatile talent for building than the wasp. In these cabinets we may trace all gradations of texture, from the flimsiest lace work, which must not be touched by unwary hands, to the cardboard box, which might lie about the nursery without damage. without damage. Brittle mud, and tough fibre, all alike, each in their turn, are put in requisition by these little architects. Chartergus hides her cells with a cover which needs a knife to get

through it; Polistes, with many others, makes no cover at all. As a rule the combs of wasps are placed horizontally, but Nectarinia builds her's in concentric segments of a sphere. Strength and attention to mechanical considerations mark most of the nests, but Icaria builds out into space quite regardless of these. Synaca spreads a smooth polished roof over her single stage of cells, which she boldly hangs out from a bough, while Polybia seeks the protection of a large leaf, or of the back of a tree to cover the mouths of the cells. In most instances the rain-drip is carefully provided against, and the surface is freed from all needless points, but Myrapetra covers her house with tubercles whose object is quite inexplicable. Each has its own fixed rule.* Whether the surface be smooth or rough, whether the entrance be central or lateral, whatever the habit be, the habit is unvarying, and the style of architecture in all its details is absolutely typical of the insect, as typical as the Phoenician bevel or the Norman mouldings. So I make no apology for devoting a whole chapter to the consideration of the architecture of the comb and the case of our British Vespa in all its typical exactness.

With the first promise of Spring, with the violet and the primrose, with the snake and the bee, on the same bank, from which the warmth of the sun has called them all forth, the mother wasp enters on active life. During the cold wet winter months she

* De Saussure, op. cit., and Möbius, 'Die Nester der geselligen Wespen,' 4to, Hamburg, 1856, have made the mode of construction of the nest the basis of a system of classification of Social Wasps.