93 
former pail of this chapter. Their reign will be 
readily recognized by the exhibition of cmded 
leaves and crippled young branches, which are 
caused by the insect lacerating them in procuring 
or extracting the juices from them j and when 
trees are numerously visited by them, their depre- 
dations not only cause the leaves to present an un- 
healthy appearance, but actually prove very inju- 
rious to the whole tree. The size of the fruit 
is diminutive, and in flavour worth but little ; and 
I have known trees, thus infested, to be at least 
three years in recovering their proper health and 
vigour. 
It is almost universally contended, and re- 
corded by several authors, that the weakest trees, 
or weakest parts of trees, are principally attacked 
in preference to the more luxuriant. These are 
opinions with which I certainly cannot coincide. 
My investigations have led me to believe, that the 
most healthy parts are equally liable to their at- 
tacks ; and I think it is probable that those mis- 
apprehensions may arise from neglect of more 
close observation, and rest only on the sup- 
position that because the weak suffer the most 
they must be most resorted to. If, however, we 
suppose the weak and the strong to be equally 
attacked, we shall find, as a matter of course, the 
effect of the depredations will be much sooner 
and more plainly exhibited on the weak than 
upon the strong ; for the latter must afford a 
greater share of 2^rovision to their depredators, and 
