INSECTS INJURIOUS TO FRUITS. 



INSECTS INJURIOUS TO THE APPLE. 



ATTACKING THE EOOTS. 

 No. 1. — The Apple-root Plant-louse. 



Schizoneiira lanigera (Hausm.). 



This insect appears in two forms, one of which attacks 

 tiie trunk of the apple-tree (see No. 9), the other works 

 under the ground and produces on the roots wart-like swell- 

 ings and excrescences of all shapes and sizes. These deformi- 

 ties seriously diminish the normal supply of nourishment for 

 the tree, and where very numerous induce gradual decay of 

 the roots, and occasionally result in the death of the tree. 

 Upon close examination the excrescences are found to con- 

 tain in their crevices very minute pale-yellow lice, often ac- 

 companied by larger winged ones. The former have their 

 bodies covered with a bluish-white cottony matter, having 

 the appearance of mould, the filaments of which are five or 

 six times as long as the insects themselves, and are secreted 

 from the upper part of the body, more particularly from 

 the hinder portion of the back. In Fig. 1, a represents a 

 knotted root, b a wingless louse, and c a winged specimen. 

 The insects are both magnified ; the short lines at the sides 

 indicate their natural size. 



The apple-root plant-louse is believed by some entomolo- 

 gists to be a native insect, while others hold to the opinion 

 that it has been imported from Europe. It is nourished by 

 sucking the juices of the tree, piercing the tender roots with 



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