AGRICULTURAL EXPERIMENT STATION. 



117 



EXPLANATIONS. 

 By a perfect insect {Imago) is meant the form that lays the eggs. 

 It is usually provided with wings, though the females of the bark 

 lice and most plant lice, and the females of the fall canker-worm 

 are wingless. The egg hatches into the larva, i. e., the caterpillar, 

 worm, grub or maggot, as the ease may be. The larva changes to 

 the pupa or chrysalis, which is the inactive or resting stage, and from 

 the pupa the perfect insect comes forth. An insect in making a 

 complete life history, would pass through four stages ; the egg, 

 larva, chrysalis and imago. The larva is the form that usually does 

 the damage. Unless otherwise stated the cuts shown are natural 

 size. When the insect is shown enlarged the natural size is usually 

 indicated by hair lines. 



THE ROUND-HEADED APPLE-TREE BORER. 



Saperda Candida, Fabr. 

 Complaints of injuries done b}' this common pest have been 

 received from various parts of the State. One writer stated that 

 he had taken fifteen larvae from a single tree. The Round-headed 

 Apple-tree Borer is a native of America and though it seems to 

 prefer the apple, is known to affect the native crab, sugar-pear, 

 thorn bushes, pear, quince and mountain-ash. It is widely distri- 

 buted and does much damage unless carefully watched. 



DESCRIPTION. 



Perfect insect — A beetle about three-fourths of an inch long, with 

 two broad white strips above running the whole length of the body — 

 hoary white below, light brown above — legs and antennae gray. 

 (Fig. l,c.) 



Larva — One inch long when full grown — footless. Whitish with 

 a round chestnut colored head, polished and hornlike and armed 

 with two black jaws. (Fig. 1, a.) 



FIG. 1. 



