Remarkable Spider Nests in the British Museum-Seed-nests and Leaf-nestsNests of the TUFTED SPIDER-Form and colouring of the Spider-Its curious limbs-Nests illustrative of the hexagonal principle-Nest of the ICARIA-The equal pressure and excavation theories-Nest of MISCHOCYTTARUS and its remarkable form-Nest of the RAPHIGASTER-Summary of the Argument-The PROCESSIONARY MOTH-Reasons for its name-How the larvæ march-Damage done by them to trees-A natural remedy-The CALOSOMA and its habits-The GIPSY MOTH-Its ravages upon trees and mode of destroying it-The social principle among Caterpillars-Mr. Rennie's experiments-The LACKEY MOTH -Supposed derivations of its popular name-The eggs, larvæ, and perfect insects-Habits of the Moth-The BROWN-TAILED MOTH-Locality where it is found-Its ravages abroad-Nests of the ICARIA as they appear in branchesThe APOICA and its remarkable nests-Moth Nests from Monte Video.

We have already seen several nests built by SPIDERS, some of which are made in the earth, others are strictly pensile, and others may fairly come into the present group. The specimens

from which the drawings were made are in the collection of the British Museum, some in the upper and others in the lower rooms. Of the architects, the manner in which the nests were made, and the reasons why they were so singularly constructed, I can say nothing, because no record is attached to the specimens. Still, they are so curious that they have found a place in this work, and it is to be hoped that the very fact of their publicity will induce travellers to search for more specimens and to describe their history.

Differing as they do in shape, colour, and material, they have one object in common, namely, the rearing of the young. They are clearly nests in the true sense of the word, being devoted not to the parents, but to the offspring. At the upper part of the illustration may be seen a number of long, spindle-shaped bodies, suspended from a branch. These are drawn about half the full size, in order to allow other specimens to be introduced into the same illustration for the purpose of comparison. In colour they are nearly white, with a slight yellowish tinge, and are very soft and delicate of texture, so that when viewed in a good light they form a very striking group of objects.

In the opposite upper corner of the illustration may be seen a remarkable nest, which few would recognise as the work of a spider. Such, however, is the case, the creature being urged by instinct to take several concave seed-pods, and to fix them together as seen in the drawing. The seed-pods are fastened firmly together with the silken thread of which webs are made, and in the interior the eggs are placed. The drawing is reduced about one-third in proportion to the actual object. Several of these singular nests are in the collection at the British Museum,

Occupying the lower part of the illustration is seen a leaf upon which are piled a number of fragments of leaves, so as to form a rudely conical heap. This is also the work of a spider, and is made with even more ingenuity than the two preceding specimens. In the first instance, the spider has spun a hollow case of silk, similar in principle of construction, though not in form, to the spherical egg cases made by several British spiders. In the second instance, the creature has chosen a number of concave seed-pods, and, by adjusting their edges together and fastening them with silk, made a hollow nest, which only requires to be lined in order to make it a fit nursery for the young. But, in

the present example, the work of nest-making has been much more elaborate, for the structure has been regularly built up of a great number of pieces, each being arranged methodically upon the other, very much as children in the streets build their oystershell grottoes. The labour must have been considerable, even if the spider had nothing to do but to arrange and fasten together pieces of leaves which had already been selected.

THE large, oval, cocoon-like nests which are seen in the accompanying illustration are made by the TUFTED SPIDER of the West Indies, a creature which derives its name from the remarkable tufts of stiff, bristle-like hairs which decorate the limbs. A very fine specimen of this remarkable Spider is now before me, having been taken out of its bottle with extreme

difficulty, owing to the great length of the limbs, and the weight of the prolonged abdomen.

The length of the body is one inch and a half, of which measurement the abdomen alone occupies two-thirds. The average circumference of the abdomen is five-sixths of an inch; and, as it varies very little thoughout its entire length, that portion of the body is very solid and heavy. The colour is deep chocolate-brown, curiously marked with circular dots of bright yellow, and further diversified with stripes of the same colour, especially over the fore-part of the abdomen. Two bold yellow bars are also drawn transversely across the under surface of the abdomen. The thorax is deep brown, and clothed with short hairs of greyish yellow, set so densely that the dark colour of the thorax cannot be seen without close inspection. There are, however, three black squared spots on each side, and a black spot occupies the centre. The animal is armed with a formidable pair of poison-jaws, of a deep shining black, at the ends of which the curved fangs are bent inwards like the venomous teeth of the rattlesnake. On the front of the thorax, and looking directly forward, are the eight eyes, the four smallest being arranged closely together in the centre, in the form of a square, and the four largest being set on bold prominences so as to form a large oblong, in the centre of which is the square.

The limbs are of considerable length. The first pair of legs, which are the longest, measure two inches and a half in length, and the expanded second pair measure four inches and a half. The most remarkable point about the spiders is the peculiarity from which it derives its name. The first, second, and fourth pairs of legs are adorned with dense hairy tufts, the first pair having two tufts each, and the others only one. The third pair of legs are much shorter and smaller than the others, and are destitute of tufts. As the legs themselves are bright yellowbrown and the tufts are deep black, the contrast of colour is very bold and agreeable to the eye. The entomological reader may perhaps remember that social exotic beetles are also decorated with tufts upon their antennæ and limbs. Of the curious spherical spider nests, with their black cross bars, nothing is known except the mere fact of their existence. as large as full-sized black currants.

They are about

IN the accompanying illustration three most remarkable nests are given, all of them the work of hymenopterous insects, and all serving in some degree to illustrate the hexagonal system of cell-building, so common among the hymenoptera.

Of these, perhaps, the central figure is the most interesting, because it entirely sets at rest a question which is periodically agitated. It is made by an insect belonging to the genus Icaria. Perhaps my readers may remember that on page 429, the celebrated bee-cell problem is described, and that mention is made of the many theories which have been invented to solve the riddle. Among them the two most conspicuous are those which are known as the equal pressure theory and the excavation theory. Differing as they do in many respects-one attempting