THE APHIS. 



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wings half crustaceous, and half membranaceous, not divided 

 by a longitudinal suture, but incumbent on each other. The 

 generic character is : — Snout inflected ; abdomen two-horned. 

 The antennae or feelers are longer than the thorax ; the wings 

 are four, and erect, or they are wanting ; the feet are of the 

 ambulatory kind ; and the belly often ends in two horns, from 

 which is ejected that most delicate juice called "honey-dew." 

 The number of species is unknown. 



These insects live entirely on vegetables. The loftiest tree 

 is no less liable to their attacks than the most humble plant. 

 They prefer the young shoots on account of their tenderness ; 

 and on this principle often insinuate themselves into the very 

 heart of the plant, and do irreparable mischief before they are 

 discovered. But for the most part they beset the foliage, 

 and are always found on the under side of the leaf, which they 

 prefer, as it protects them from the weather, and other in- 

 juries to which they would otherwise be exposed. They also 

 attack the roots and the bark. Some of the "aphides," as of 

 caterpillars, are general, and others are particular feeders ; 

 and, like other insects, are more abundant in some years than 

 in others. They are very common on hop plants, beans, peas, 

 and sometimes on potatoes, and on most forest trees and 

 shrubs. They appear in the spring with the first budding of 

 the earliest plants, and proceed from small black oval eggs, 

 which were deposited on last year's shoot ; if they come too 

 soon, the frost often destroys them all. Those that withstand 

 the severity of winter, are full-grown in April, when they 

 begin to breed, after twice casting off their exuviae, or outer 

 covering. Generation succeeds to generation during the sum- 

 mer, and the increase is very great. They have many ene- 

 mies, or the number would become beyond endurance. 



The " Aphis," by puncturing the tender leaves of plants, 

 draws the juice to the wounded part, and exhausts it. The 

 plant is thus deprived of the proper nourishment by circulation. 

 Many plants grow deformed by the number of punctures 

 made upon their leaves, and decay from want of the usual 

 sap. Some thrive even when covered with these insects ; 

 while others rise up into small hollow tubercles, which, on 



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