410 INSECTS INJURIOUS TO VEGETATION. 



Cimbex Vlmi, because she inhabits the ehn. The male is the 

 Cimbex Americana of Dr. Leach, and differs so much from 

 the female, that it might be taken for a different species. His 

 body is longer and narrower than that of the female, and 

 wants the white spots on the sides; and there is a transverse, 

 oval hole, filled with a whitish film, behind the thorax, which 

 is hardly perceptible in the other sex. His hind legs are very 

 thick; the shins are bowed, and hairy within; and the first 

 joint of his feet ends with a stout hook, curved inwards. He 

 often measures an inch in length, and his wings expand about 

 two inches. These insects appear from the latter part of May 

 to the middle of June, during which period the female lays 

 her eggs upon the common American elm, the leaves whereof 

 are the food of her young. The latter come to their growth 

 in August, and then measure from one inch and a half to two 

 inches in length. They are rather thick, and nearly cylindrical 

 in form, and have twenty-two legs, or a pair to every ring 

 except the fourth. They have a firm, rough skin, of a pale 

 greenish yellow color, covered with numerous transverse WTin- 

 kles, with a black stripe, consisting of two narrow black lines, 

 along the top of the back, from the head to the tail; and their 

 spiracles, or breathing-holes, are also black. When at rest, 

 they lie on their sides, curled up in a spiral form, and, in this 

 position, look not much unlike some kinds of cockle or snail 

 shells. Like all the false caterpillars of the genus Cimbex, 

 this insect, when handled or disturbed, betrays its fears or its 

 displeasure by spirting out a watery fluid from certain little 

 pores situated on the sides of its body just above its spiracles. 

 After its feeding state is over, it craAvls down from the tree to 

 the ground, and conceals itself under fallen leaves or other 

 rubbish, and there makes an oblong oval, brown cocoon, very 

 closely woven, as tough as parchment, and about an inch 

 in length. In this the false caterpillar remains unchanged 

 throughout the winter, and is not transformed to a chrysalis 

 till the following spring. At length the insect bursts its chry- 

 salis skin, and, by pushing against the end of its cocoon, forces 

 off a little circular piece like a lid, and through the opening 

 thus made it comes forth in its winged form. 



