80 INSECTS INJURIOUS TO THE APPLE. 



lish alder, red currant, and hazel ; also on the hickory, birch, 

 elm, honey-locust, barberry, hawthorn, and elder. 



During the winter their cocoons should be looked for and 

 destroyed ; the larvae also may be subdued by hand-picking, — 

 their work, as well as their appearance, being so conspicuous 

 that they are readily detected. 



No. 29. — The Unicorn Prominent. 



Ccelodasys unicornis (Sm. & Abb.) 



The larva of this moth is a very singular-looking creature. 

 (See Fig. 78.) It is reddish brown, variegated with white, on 

 the back, with a large brown head ; the 

 Fig. 78. sides of the second and third segments 



are green, and from the top of the 

 fourth a prominent horn is projected. 

 There are on the body a few short 

 hairs, scarcely visible to the naked eye ; 

 the posterior segment, with the hindermost pair of feet, is 

 always raised when the insect is at rest, but it generally uses 

 these feet in walking. In August and September this larva 

 may be found nearly full grown. At first eating a notch, 

 about the size of its body, in the side of the leaf on which it 

 is feeding, and placing itself in this notch, with the humps 

 on its body somewhat resembling the irregularities in the 

 margin of the partly-eaten leaf, it is not easily detected. 

 Eventually it consumes the entire leaf, except a small portion 

 of the base. When mature, it measures from an inch to an 

 inch and a quarter in length, and, while generally solitary in 

 its habits, sometimes three or four are found together eating 

 the leaves of the same twig. Besides the apple, it feeds on 

 the plum, dogwood, rose, alder, and winterberry. 



Wiien full grown, which is towards the end of September, 

 it descends from the tree, and under fallen leaves on the 

 ground constructs a thin, almost transparent, papery cocoon, 

 with bits of leaves attached to the outside. A considerable 

 time elapses after the cocoon is formed before the caterpillar 



