ORDER II. BUGS. 83 



Plant-lice (Aphis). 



Like the preceding insects, the PlaBt-lice belong to the 

 order of Bugs which constitute the Hemipterous Insects. 

 They have small round bodies, of a brown, black, yellow, 

 or blue color. Some species are provided with wings, some 

 others have none ; but on the back of all of them may be 

 seen two honey-tubes, or honey-warts, from which issues a 

 sweet substance very much liked by the Ants. For this 

 reason we find even such carnivorous insects as the Ants on 

 friendly and intimate terms with the Plant-lice. In fact, 

 they are called the milk-cows of the Ants, because the lat- 

 ter suck from them the sweet juice of their honey-tubes. 

 They are as careful of them as we of our cows, protect 

 them from their enemies, and, in case of danger, even carry 

 them away in their mouth very carefully to a safe place. 

 This sweet fluid of the Plant-lice is also often seen upon 

 the branches of trees or shrubs a glutinous substance 

 known by the name of honey-dew, and eagerly sought by 

 Ants. If, therefore, we see Ants running up and down the 

 branches of trees and shrubs, we may consider it a certain 

 indication of the presence of Plant-lice. 



There is scarcely a tree, or bush, or herb that grows in 

 our gardens or fields that is not infested with some species 

 of Plant-lice ; and in spite of their diminutive size, and 

 the disgust we naturally have for them, a host of interest- 

 ing associations are connected with them. Their manner 

 of living, and of reproduction also, have attracted much 

 interest. They both deposit their eggs and bring forth 

 their young alive a phenomenon which does not take place 

 in any of the four-winged insects. Their multiplication is 

 immense, and, considering the size of the animal, realty as- 

 tonishing ; for it is a well-known fact that one single Plant- 

 louse is capable of producing ninety young ones, from which 

 spring myriads more. From the month of April to No- 



