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ENTOMOLOGY, 
ENTOMOLOGY. 
The next insect whose depredations are seriously injurious to fruit 
trees and other plants, is what is commonly called the Red Spider. 
Acarus tcilarius , Lin. This however is a misnomer, as the insect is not 
a spider at all; but because they have the power of forming something 
like a web, when allowed to remain long on the same leaf, they 
have had this name given them. They belong to the apterous genus 
Acarus of Linnaeus, and of which there are many species, some of 
them so exceedingly minute as to be scarcely visible to the naked 
eye. One species, supposed to be particularly partial to the leaves 
of kidney-beans, will however leave this food for the delicate skin of a 
young lady or child, into the pores of which they will insinuate their 
little beaks, and seat themselves for days together, causing considerable 
irritation and inflammation, and at the same time safe from every effort 
of the sufferer to dislodge the little pest, or even to see, without a 
magnifying-glass, the cause of the teasing sensation. This is called 
the Harvest-bug , by those who perhaps never saw the insect, or 
know that they may be extracted by the point of a muslin needle. 
The gardener’s enemy is a size larger than this; but they are much 
oftener discovered by their depredations, than by their bulk, either 
individually or collectively. When very young they are colourless, 
when half grown they are red, and when full grown dark brown. 
They infest peach, nectarine, and vine trees, both in the house and in 
the open air; and are often troublesome in hotbeds, on the leaves of 
cucumbers and melons. Stove-plants are particularly subject to them, 
and especially on some of the spinous succulents, which neither admit 
of them being brushed or washed off. 
This insect injures plants by puncturing the cuticle of the leaves 
and tender shoots, and very probably by sucking the juices, as after 
their attack the leaves become paler, and cease to have a healthy 
appearance. Indeed, the whole tree puts on a sickly habit, and con¬ 
sequently the fruit are small and tasteless. When suffered to increase 
and establish themselves, on a vine-leaf for instance, they make for 
themselves little bridges of fine silk-like webs, from one prominence 
on the surface of the leaf to another, along which they journey for¬ 
wards and backwards. The web seems to be a defence against 
moisture, but whether it be spun from the mouth, as by some caterpillars, 
or from the abdomen, like the common spider, is uncertain. It is 
not intended, like that of the spider, for entrapping prey, but rather as 
a kind of dry nest for their eggs or young. 
Water and a moist atmosphere is their bane, and more especially if 
