ATTACKING THE LEAVES. 123 



the under side of the head, is here hidden from view in the 

 male, but can be seen in the female. 



The winged females and the males are very similar in color. 

 The head, thorax, and antennae are black, with the neck usually 

 green. The abdomen is short and thick, of an oval form 

 and bright- green color, with a row of black dots along each 

 side; the nectaries and tail-like appendage are black; the 

 wings are transparent, with dark-brown veins. 



Most of the insects belonging to this family are provided 

 with two little tubes or knobs, which project, one on each 

 side, from the hinder part of their bodies ; these are called 

 honey-tubes, or nectaries, and from them is secreted in con- 

 siderable quantities a sweet fluid. This fluid falling upon 

 the leaves and evaporating gives them a shiny appearance, as 

 if coated with varnish, and for the purpose of feeding upon 

 this sweet deposit, which is known as honey-dew, different 

 species of ants and flies are found visiting them. Ants also 

 visit the colonies of aphides and stroke the insects with their 

 antennae to induce them to part with vsomeof the sweet liquid, 

 which is greedily sipped up. This fluid is said to serve as 

 food for a day or two to the newly-born young. 



The leaves of trees infested by these insects become dis- 

 torted and twisted backwards, often with their tips pressing 

 against the twig from which they grow, and they thus form, 

 a covering for the aphides, protecting them from rain. An 

 infested tree may be distinguished at some distance by this 

 bending back of the leaves and young twigs. It is stated 

 that the scab on the fruit of the apple-tree often owes its 

 origin to the punctures of these plant-lice. This species, 

 which was originally imported from Europe, is now found 

 in apple- orchards all over the Northern United States and 

 Canada. 



Remedies, — Scraping the dead bark off the trees during the 

 winter and washing them with a solution of soft soap and soda, 

 as recommended for No. 2, the two-striped borer, would be 

 beneficial, by destroying the eggs. Syringing the trees, about 



