27 



From the brief description of the female moth given above it will 

 be seen that she differs widely from those of the two species men- 

 tioned above, both of which resemble her in being entirely destitute 

 of wings. The female Fall Canker-worm Moth is of a uniform dark- 

 gray color, unmarked ; the legs are ash-gray. The female Spring 

 Canker-worm Moth is of a pale-gray color, marked on the back 

 with a black stripe which is sometimes nearly divided in the middle 

 by a whitish line or a row of whitish spots ; the legs are ringed 

 with black and gray. The caterpillars, or worms, differ from each 

 other still more widely than the female moths do. The Fall Canker- 

 worm ia provided with twelve legs, one pair of horny texture, under 

 each of the first three segments back of the head, and one pair of 

 soft, fleshy pro-legs under the eighth, ninth and last segments. The 

 Spring and the Yellow Canker-worms are provided with only ten 

 legs, the eighth segment being entirely destitute of legs. The Spring 

 Canker-worm is of a greenish color, marked on each side with four 

 whitish lines ; the head is mottled, pale on the top, and marked on 

 the face with two pale lines running crosswise. The Yellow Canker 

 worm, as its name indicates, is of a yellow color, marked on the 

 back with ten black lines ; these lines sometimes impart a bluish 

 cast to the ground color, but diere is always a stripe of bright yel- 

 low beneath the lowest line ; the head is yellowish-brown. 



MIGRATION OF THE SPECIES. 



It sometimes happens that orchards which are situated at some 

 distance from any other orchard, and from shrubs and trees of any 

 kind, will suddenly become infested with these pests. The female 

 moths being wingless, the question natually arises, "How do they 

 migrate from so great a distance?" It is my opinion that these 

 migrations are performed by the male moths during copulation. 

 Being provided with ample wings they could readily transport the 

 females to quite a distance. We frequently see . this among the 

 Butterflies, and why may we not look for it among the Moths, es- 

 pecially among those the females of which are wingless. 



NATURAL ENEMIES. 



The Yellow Canker-worms are preyed upon by quite a number of 

 birds, particularly the Blue-Jay {Cyanura cristata), which feeds its 

 young largely upon these and other naked caterpillars. The young 

 worms are preyed upon by the larvse of the Fifteen-spotted Lady- 

 bird {Anatis 15-punctata, Olivier). The Green and the Ked spotted 

 Caterpillar hunters {Calosnia scrutator, Fabricius, and Galosma cali- 

 dum, Fabricius), destroy many of them, especially the former, which 

 I have frequently found climbing about in the tops of the trees in 

 search of them. The Dotted-legged Plant-bug {Euschistus pimctipes, 

 Say), also feeds upon them, as I have frequently seen it clinging to 

 the underside of a limb with one of these Canker-worms danghng 

 from its beak. Dr. Packard says of the group to which this insect 

 belongs* {Pentatomdae) that they are "found on shrubs, sucking the 

 leaves, or often transfixing caterpillars on their beaks and carrying 



*Guide to the Study of Insects, pg. 546. 



