548 THE SCALE INSECT, OK MEALY BUG. 



several old-established opinions, and in all probability will serve, when fully investigated, 

 in establishing a new basis on which to found a more perfect system. The Aphides are 

 wonderfully prolific, crowding upon plants until they completely hide them from view, 

 and all employed in sucking the juice by means of the peculiar beak. They haunt every 

 part of the plant, the leaves and their stalks, the branches, and even the roots being 

 infested by these persevering destroyers, which often do great damage, and even force the 

 leaves and branches to twist themselves into extraordinary contortions. Some species 

 raise certain excrescences which serve as habitations for the insects. 



In many species there is a pair of tubercles towards the extremity of the insect, 

 which exude a sweetish liquid in a manner analogous to the frothing of the cuckoo-spit. 

 This liquid falls upon the leaves of trees and is then known by the name of honey-dew. 

 Bees are very fond of this substance, and, wherever it is present in any quantities, may be 

 seen licking up the sweet secretion. Ants are equally fond of honey-dew, but they go to 

 the fountain-head at once, and lap it as it flows from the tubercles. Whole regiments of 

 ants may be seen ascending trees in search of the Aphides ; and it is very amusing to see 

 how they will search every atom of a tree on which the Aphides live, so as not to allow 

 a single insect to escape them. 



The white, cottony substance that is found upon the trunks of apple-trees, and is 

 popularly called the Apple Blight, is produced by one of the Aphides called popularly 

 the American Blight, and known to naturalists under the title of Lachnus lanigerus. In 

 some species the beak or proboscis is of enormous length, three times as long as the body, 

 and projecting like a tail as it is held folded under the body. 



Many species of Aphis are winged, although every individual does not require those 

 organs, being born, developed, producing a family, and then dying without requiring 

 wings, or even moving from the spot whereon it lived. One of the most curious circum- 

 stances connected with these insects is, that although, like all insects, the sexes are 

 distinct, it often happens that the presence of a male is quite needless in the production 

 of a family, at least nine generations of fertile females having been successively produced 

 within three months. One colony of the Aphis Dianthi continued to increase for a space 

 of four years, without a single male among their number ; and it seems generally to be 

 the case that the males are not produced until the end of the summer, the only espousals 

 required being those of the last generation of the year. These lay eggs, which are 

 hatched in the succeeding spring, and from them pours an uninterrupted succession of 

 females, a veritable colony of Amazons, who have no husbands, and millions of which 

 die the mothers of countless descendants, without ever having seen a member of the 

 opposite sex. 



THE right-hand upper figure in the illustration represents the winged male of a small 

 but very remarkable insect, known scientifically as the Coccus, and popularly as the 

 SCALE INSECT, or MEALY BUG, the former title being applied to the exterior of the female, 

 and the latter given on account of the white mealy substance that is found within her 

 body. These insects are sad pests to gardeners, infesting various fruit trees, and increasing 

 with such rapidity that their progress can scarcely be checked. The young, too, are of 

 such minute size that they can hardly be seen or destroyed. It appears, however, that 

 the most effectual way of checking their depredations is to make a kind of semi-liquid 

 paste of fine clay and water, and with a brush to wash it well into the bark of the 

 affected trees, so as to cover the insects, deprive them of air, and debar them from 

 removing. Three or four coats are necessary, in order to stop up the minute cracks which 

 are sure to take place in the drying clay, and which would afford ample opportunities of 

 egress to these tiny creatures. 



When the young first make their appearance in the world, they are minute six-footed 

 creatures, with antennae, and two long hairs attached to the tail. The sexes resemble 

 each other until the time comes for their change into the pupal state, when the males 

 assume a quiescent condition, and are covered by a cocoon-like envelope. At the proper 

 time they leave the cocoon, and are then seen to be little flying creatures, with only two 

 active wings, the hinder pair being merely indicated by a couple of small projections. 



