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Seciul Relations betuceen duts and Vegetation.--licention has recently been called to the very remarkiille rolations existing between some trees and shrub- anal the ants which wol upon them. In the Marley Islands are several curious sbruls belonging to the Cinchonanceir, which grow parasitically on other ares, ?m whose swollen stems are veritable ants' 14.st. When very yomg the stems are like small, irrazili pribly tubers, in the hollows of which ants consibilisha then. :vrs; and these pil time grow into irreglin. Bi es die size of Parga godzils, completely lovesromind with the cells of ants. In America there are some amalayous cases Ocruring na several families of plants, one of the most remarkable being that of contain Mclastomas which have a kind of pouch formed by an enlargement of the petiole of the leaf, and which is inhabited by a colony of small ants. The hollow stems of the Cecropias (curious trees with pale bark and large palmate leaves which are white beneath) are always tenanted by ants, which make small entrance holes through the bark; but here there seems no special adaptation to the wants of the insect. In a species of Acacia observed by Mr. Delt, the thorns are immensely large and hollow, and are always tenanted by ants. When young these thorns are soft and full of a sweetish pulpy substance, so that when the ants first take possession they find a store of food in their house. Afterwards they find a special provision of honey-glands on the leaf-stalks, and also small yollow fruit-like bodies
which are eaten by the ants; and this supply of food permaneutly attaches them to the plant. Vr. Belt believes, after much careful observation, that these ants protect the plant they live on from leaf-eating insects, erecally from the destructive Saiba ints, ---Ulat they are in fact in stiindling army kept for the protertion of the plant! This view is supported by the fact that other plants--Passion-flowers, for example—have honeysecreting glimds on the young leaves and on the sepals of the lower-bulls which constantly attract a small black ant. If this view is correct, we see that the need of escaping from the destructive attacks of the leafcutting ants bas led to strange modifications in many plants. Those in which the foliage was especially attractive to these anemies were soon wecileil out unless variations occurred which tended to preserve them. llence the curious plonomenon of inserts sperially attracted to certain plants to protect them from other insects; and the existence of the destructive leaf-cutting ant in America will thus explain why these specially modified plants are so much more abundant there than in the Old World, where no ants with equally destructive habits appear to exist. .
Wasps and Bees. These insects are excessively numerous in the tropies, and, from their large size, their brilliant colours, and their great activity, they are sure to attract attention. Handsomest of all, perhaps, are the Scoliadae, vhose large and rather broad hairy bodies, often two inches long, are richly bandel with yellow or orange. The Pompilidae comprise an immense number of large and handsome insects, with rich blue-black bodies and wings and exceedingly long legs. They may often
WASPS AND BEES. be seen in the forests dragging along large spilers, beetles, or other insects they have captur-. Some of the smaller species enter bouse's und builil carthen cells which they store with small groen spilers rendered torpid by stinging, to feed the larvæ. The Eumenidlæ are beautiful wasps with very long perlusculated bwies, which build paperv cones covering a few cells in which the eggs are depositul. Among the bees the Xylocopas, C. Tromel-boring bees, are l'imarhable. They resemble Targe humble-bees, but have broad, flat, shining bodies, cither black or banded with blue; and they oiten bore litere cylindrical holes in the posts of houses. True honey-lices are chietly remarkable in i Eilst for their large semi-circular coml; suspended from ile branches of the loftiest trees without any covering. From thiese exposed re-t3 large quantities of wax and honey are olitained, while the larve allurid a rich feirst to the natives of Borneo, Timor, and other islands where bees abound. They are very pugnacious, ind, when disturbed will follow the intruders for miles, stinging severely.
Orthoptera and other Insects.- Next to the butterflies and ants, the insects that are mont likely to attract the attention of the stranger in the tropics are the various forms of Mantidæ and Phasmide, some of which are remarkable for their strange attitudes and bright colours ; while others are among the most singular of known insccts, owing to their resemblance to sticks and leaves. The Mantidæ-usually called “priying insects,” from their habit of sitting with their long fore-feet held up as if in prayer-are really tigers among insects, lying in wait for their prey, which they seize with their powerful serrated fore-feet. They are usually so coloured as to
resemble the foliage among which they live, and as they sit quite motionless, they are not casily perceived.
The Phy:tsmidze are perfectly inoffensive leaf-eating insects of very varied forms ; some being broad and leaf-like, while others are long and cylindrical so its to resemble sticks, whence they are often called walking-stick insects. The imitativi simblance of some of these insects to the plants in bila they live is marvellous. The true leafinsets of the East, forming the genus Phyllium, are the size of a moderate leaf, which their large wing-covers and the dilated margins of the head, thorax and legs cause them exactly to resemble. The vining of the wings, and their groen tint, exactly corr els to that of the leaves of their tool-plant; and as they rest motionless during the day, only f ing at night, they the more easily escape detertion. In Juva they are often kept alive on a branch of the unava tree; and it is a common thing for a stranger, when asked to look int this curious insect, to inquire where it is, and on being toll that it is close under his eyes, to maintain that there is no insect at all, but only a branch with green leaves.
The larger wingless stick-insects are often ciglit inches to a foot long. They are abundant in the Moluccas; hanging on the shrubs that line the forest-paths; and they resemble sticks so exactly, in colour, in the small rugosities of the lark, in the knots and small branches, imitated by the joints of the legs, which are cither pressed close to the body, or stuck out at random, that it is absolutely impossible, by the eye alone, to distinguish the real dead twigs which fall down from the trees overhead from the living insects. The writer has often looked at them in doubt, and has been obliged to use the sense of
touch to determine the point. Some are small and slender like the most delicate twigs ; others again have wings; and it is curious that these wings are often beautifully coloured, generally bright pink, sometimes yellow, and sometimes finely banded with black; but when at rest these wings folel up so as to be completely concealed under the narrow wing-covers, and the whole insect is then green or brown, and almost invisible among the twigs or foliage. To increase the resemblance to vegetation, some of these Phasmas have small green processes in various puerts of their bodies looking exartly like moss. These inhibii damp forests both in the Milliy islands and in Imericit, and they are so marvellously like moss-grown twigs that the closest examination is needed to satisfy oneselihat it is really a living insect we are looking at.
Mans of the locusts are equally welldisguised, some resembling green leaves, others those that are brown and dead ; and the latter often have small transparent spots on the wings, looking like holes eaten through them. That these disguises deceive their natural enemies is certain, for otherwise the Phasmidae woull soon be exterminated. They are large and sluggish, and very soft and succulent; they have no means of defence or of flight, and they are cagerly devoured by numbers of birds, especially by the numerous cuckoo tribe, whose stomachs are often full of them ; yet numbers of them escape destruction, and this can only be due to their vegetable disguises. Mr. Belt records a curious instance of the actual operation of this kind of defence in a leaf-like locust, which remained perfectly quiescent in the midst of a host of insectivorous ants, which ran over it without finding out that it was an insect and not a leaf! It might have