118 THE PESTS OF THE FARM. 



before laying its eggs, it uses its short curved snout, which is armed 

 at the tip with a pair of very small nippers ; and by means of this 

 weapon, ; t makes, in the tender skin of the young plum or apple, 

 a crescent-shaped incision, similar to what would be formed by in- 

 denting the fruit with the finger nail. Very rarely is there more 

 than one incision made in the same fruit ; and in the wound, the 

 weevil lays only a single egg. The insect hatched from this egg 

 is a little whitish grub, destitute of feet, and very much like a mag- 

 got in appearance, except that it has a distinct, rounded, light brown 

 head. It appears, furthermore, that the tumors on plum and on 

 cherry trees are infested not only by these insects, but also by an- 

 other kind of grub, provided with legs, and occasionally by the 

 wood-eating caterpillars of the jEgeria exitiosa, or peach-tree borer. 

 When the grubs of the plum-weevil are fully grown, they go into 

 the ground, and are there changed to chrysalids of a white color, 

 having the legs and wings free and capable of some motion ; and 

 finally they leave the ground in the form of little beetles, exactly 

 like those which had previously stung 'the fruit. Further observa- 

 tion seems to be wanting before it can be proved that the cankerous 

 warts on plum and cherry trees arise from the irritating punctures 

 of the plum-weevils and of the other insects that occasionally make 

 these warts their places of abode ; although it must be allowed that 

 the well-known production of galls by insects on oak-trees and on 

 other plants, would lead us to suppose that those of the plum-tree 

 have a similar origin. 



CANKER-WORMS. The insects called canker-worms are of a kind 

 called Span-worms, or Geometers, and of the group Hybernians. 

 The moths, from which they are produced, belong to the genua 

 Anisopteryx. 



It was formerly supposed that the canker-worm moths came out 

 of the ground only in the spring. It is now known that many 

 of them rise in the autumn and in the early part of the winter, 

 and in mild and open winters in every month from October to 

 March. They begin to make their appearance after the first hard 

 frosts in the autumn, usually towards the end of October, and they 

 continue to come forth, in greater or smaller numbers, according 

 to the mildness or severity of the weather after the frosts have be- 

 gun. Their general time of rising is in the spring, beginning about 

 the middle of March, but sometimes before, and sometimes after 

 this time ; and they continue to come forth for the space of about 

 three weeks. It has been observed that there are more females 



