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worthy of trial, we must then endeavour to aid Nature in her efforts to restore the equili- 

 brium, after -which she is ever striving, by encouraging and protecting insect friends, 

 which prey on the destructive species, also insectivor-ous birds and other useful agencies ; 

 in short, learn to distinguish our friends from our foes, and strive to protect the former 

 while we destroy the latter. 



To make our subject clearer we shall refer somewhat in detail to the habits and 

 peculiarities of some common representative species in each of the departments referred 

 to. As representing the root-boring insects, the broad-necked Prionus, Prionus laticoClis, 

 which sometimes attacks the roots of apple and pear trees. The sap-sucking insects attack- 

 ing the root, the apple-root plant-louse, Sckizoneura lanigera. The trunk borers will 

 be represented by the maple borer, Glycobiios speciosus ; the maple egerian, Aegeria 

 acerni; the northern brenthian, Eupsalis minuta; the pigeon tremex, Tremex columba ; and 

 the hickory and walnut borer, Monohammus tigrinus. Those which injure the 

 branches, by the hickory twig girdler, Oncideres cingulatus, and the woolly louse of 

 the pine. Coccus pinicorticis. Of the hosts which attack the leaves, reference will 

 be made to the forest tent caterpillar, Clisiocampa sylvatica ; the luna moth. Actios 

 luna ; the lime-tree measuring worm, Hybernia tiliaria ; the poplar dagger-moth, 

 Acronycta lepusculina ; the pine leaf-miner, Gelechia pinifoliella ; the oak leaf-miner, 

 Lithocolletis hamadryadella ; the white pine saw-fly, Lophyrus abbotii ; and the hickory 

 aphis, Aphis caryalla. 



Attacking the Roots. 



The Broad-necked Prionus — Prionus laticollis. 



This insect bores into the roots of the apple and pear trees, and often injures the 



roots of grape vines. When 

 full grown it is a very large 

 fleshy grub, from two and a 

 half to three inches long (see 

 Fig. 1), of a yellowish white 

 colour, with a reddish brown 

 head, and a dull bluish line 

 down the back. It eats its 

 way through the centre of 

 the root, and where the root 

 it attacks is not very large, 



reduces it to a mere shell. It lives in the 



larval state some two or three years, and 



then changes to a chrysalis, as shown in 



Fig. 2, within the root ; this change occur- 

 ring in the summer season, usually towards 



the end of June. 



About the middle of July the beetle 



appears. It is of a brownish black colour, 



about an inch and a half long, with strong 



thick jaws and rather slender antennae or 



horns. It is well represented in Fig. 3. 



Its thorax is short and wide, and armed at 



the sides with three teeth ; the wing-covers 



have three slightly elevated lines on each, 



and are thickly punctured. The figure 



represents a female ; in the male the body 

 and the antennae longer. 



