422 LEPIDOPTERA. 



ably on account of the shrivelled appearance and dark color 

 of the caterpillar. In its winged state, IAmacodes pithedum, 

 or the hag-moth, as it may be called, is of a dusky brown 

 color; its fore wings are variegated with light yellowish 

 brown, and with a narrow curved and wavy band, of the 

 same light color, edged externally with dark brown near 

 the outer margin, and a light brown spot near the middle ; 

 the fringes of all the wings are spotted with light brown ; 

 the legs are covered with long hairs ; the antennae, in 

 both sexes, are slender, . almost thread-like, and not feath- 

 ered. It expands from nearly one inch to one inch and a 

 quarter. 



There is a kind of caterpillar, found in July and August 

 on the balsam poplar, and sometimes on other poplars and 

 willows, whose form, posture, and motions are so odd as 

 at once to arrest attention. Its body is naked, short, and 

 thick, tapers behind, and ends with a forked kind of tail, 

 which is held upwards at an obtuse angle with the rest of 

 the ; body. This forked tail, which takes the place of the 

 hindmost pair of legs, the others being only fourteen in 

 number, is not used with the latter in creeping, and consists 

 of two movable hollow tubes, within each of which is con- 

 cealeda long orange-colored thread, that the insect can push 

 out and draw in at pleasure. The feet are short and small ; 

 the head is small, of a purple color, and can be drawn 

 under the front part of the first ring ; the body is green, 

 with a triangular purple spot on the top of the fore part, 

 and a large diamond-shaped patch, of the same color, cov- 

 ering the back and middle of the sides like a mantle, and 

 prolonged behind to the tail. When young, these caterpil- 

 lars have, on the top of the first ring, two little prickly 

 warts, which disappear after one or two changes of the skin. 

 When teased by being touched, or irritated by flies, the cat- 

 erpillar runs out the threads from its forked tail, which it 

 jerks forwards so as to lash the sides of its body and whip 

 off the intruder. When fully grown, it measures sometimes 



