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Special Relations between ints and Vegetation. ---Itention has recently been called to the very remarkable relations existing between some trees and rul: anıl the ants which dwell upon them. In the Malay Tlands are several curious shrutos belonging to the Cinchonaret', which grow parasitically on other mes, n? whose swollen stems are veritable ants' nesti yomg the stems are like small, irregul: ( prishiy tubers, in the hollows of which ants contabilisti !ltenle rlirs; and these in time grow into irreguidoDit-lic size of large orals, completely honeycomed with the cells of
In America there are some analayous cases ocurring in several families of plants, one of the most remarkable being that of certain Melastomas which have a kinel of
pouclı formel ly an enlargement of the petiole of the leaf, and which is inhabited by a colony of small ants. The hollow stems of the C'ecropias (curious trees with pale bark and large palmate leaves which are white bencatlı) are always tenanted by ants, which make small entrance holes through the bark; but here there seems nu special adaptation to the wants of the insect. In a species of Acacia observed by Mr. Belt, the thorns are immensely large and hollow, and are always tenanted by ants. When
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 yellow fruit-like bodies
which are caten by the ants; and this supply of food permanevily attaches them to the plant. Mr. Belt believes, after much careful observation, that these ants protect the plant they live on from leaf-rating insects, especially from the destructive Saiba ants, ---that they are in fart i stiuniling army kepi for the protection of the plant! This view is supported by the fact that vther plants---Passion-flowers, for example—have honeyserriting glunds on the young leaves and on the sepals of the power-buds 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 has led to strange modifications in many plants. Those in which the foliage was especially attractive to these enemies were soon weerle out unless variations occurred wliich tended to preserve them. Hence the curious phenomenon of insects sperially attracted to certain iants 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 cqually 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 Scoliadæ, vhose large and rather broad hairy bodies, often two inches long, are richly banded with yellow or orange. The Pompilida comprise an immense number of large and handsome insects, with rich blue-black bodies and wings and exceedingly long legs. They may often
be seen in the forests «Iragging along large spilers, beetles, or other insects they have cititur i. Some of the smaller species enter houses and builul carthen cells which they store with small green lers rendered torpid ly stinging, to feel the luva. The Eumenielä are beautiful
very long perlusculated bories, which build papery cones covering a fuw cells in which the eggs are depositul. Among the bees the Xylocopas,
Wowel-boring bees, are limarhable. They resemble Jarge humble-bees, but have broad, flat, shining bodies, cither black or banded with bluc; and they oiten bore lacre cylindrical holes in the posts of houses. True honey-lices are chietly remarkable in the Exist for their large semi-circular comlis suspended from ille branches of the loftiest trees without any covering from these exposid (-t3 large quantities of wax and honey are obtained, while the larvie aífurl a rich feast to the natives of Borneo, Timor, and other islands where bees abound. They are very pugnacious, ind, when disturbed will follow the intruders for mil's, stinging severely.
Orthoptera and other Insects.- Next to the butterflies and ants, the insects that are mo-t likely to attract the attention of the stranger in the tropics are the various forms of Mantida and Phasmide, some of which are remarkable for their strange attitudes and bright colours; while others are among the most singular of known insects, owing to their resemblance to sticks and leaves. The Vantidæ—usually called “priying insects,” from their habit of sitting with their long forc-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 n't casily perceived.
The Phasmidze are perfectly inoffensive leaf-cating 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 semblance of some ! these insects to the plants all think 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-cover's and the dilated margins of the head, thorax and legs cause them exactly to resemble. The wining of the wings, and their gren tint, (xactly compils to ibat of the leaves of their 100l-plant; and as they rest motion less luring the day, only feeling at night, they the mole easily escape detertion. In Jura they are often kept alive on a branch of the gnava tree; and it is a common thing for a stranger, when asked to look at this curious insect, to inquire where it is, anil 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 cight 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 bark, in the knots and small branches, imitated by the joints of the legs, which are cither pressed close to the body, or stụck out at raudom, 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 bundled with black; but when at rest these wings fold up so as to be completely concealed under the narrow wing-covers, and the whole insect is then green or brown, ind ilmost invisible among the twigs or foliage. To increase the resemblance to vegetation, some of these l'hasmas have small green processes in various piirts of their bodies looking exactly like moss. These inhabit vlamp, forests both in the Malay islands and in Imericil, and they are so marvellously like mess-grown twig that the closest examination is need to satisfy onesti' ilat it is really a living insect we are looking at.
Ming of the locusts are equally well-disguised, some resembling green leaves, others those that are brown and dead ; and the latter often have small transparent spots on she 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 eagerly devoured by numbers of birils, especially by the numerous cuckoo tribe, whose stomachis 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