INSECTS INJURING OAK LEAVES. 117 



After four to six days the second skin is cast and the color has become still darker. 

 Head honey yellow. Cervical shield polished black. Thoracic and first abdomina' 

 segment brownish. Dorsal space light green or whitish, with the medial line and 

 subdorsal stripe white, a brown line above stigmata and broad white lateral line. 

 Venter light green. Piliferous warts white, furnished with a fine, short, pale hair. 



Four or five days later the fourth and fifth molts take place. (Riley's unpublished 

 notes.) 



INJURING THE LEAVES. 



163. The forest tent-caterpillar. 



Clisiocampa disstria Hiibner; {Clisiocampa sylvatica Harris). 



Order Lepidoptera; family Bombycid^. 



A caterpillar like the apple-tree tent-caterpillar, but difiering from it in having a 

 row of oval white spots instead of a white stripe along its back ; the colony spinning 

 a cobweb-like nest against the side of the tree; spinning a whitish cocoon, the moth 

 appearing early in July. 



The nests of this caterpillar, unlike the prominent tents of C. americana^ 

 so abundant in wild-cherry trees and neglected orchards, are seldom 

 seen, as they are of so slight a texture and are so much less conspicuous 

 objects than the tent-like whitish nests of G. americana ; but the cater- 

 pillars are not infrequently met with. After spinning, about the middle 

 of June in the Northern States, a dense, oblong cocoon, the caterpillar 

 lies in it about twenty days, the moth appearing the early part of July. 

 It occurs in the Atlantic and Southern States. Fitch states that it also 

 occurs on the apple and cherry, the walnut, and other trees. Dr. Riley 

 informs me that this is as destructive as any caterpillar to the foliage of 

 the oak in the Southern States, being far more injurious than stated by 

 Fitch, who quotes with disapproval Abbot's statement (Insects of Geor. 

 gia, p. 117) that they are "sometimes so plentiful in Virginia as to strip 

 the oak trees bare." 



Boisduval states that this species occurs rarely in California, but Mr. 

 Stretch states that " the occurrence of this species in California, or even 

 on the Pacific coast of North America, is unknown" to him. (Papilio,!, 

 68.) 



Mr. James Fletcher* reports that this tent-caterpillar was very 

 injurious in 1884 in parts of Nova Scotia and New Brunswick, "entirely 

 defoliating large tracts of hard-wood bush." 



" It feeds on leaves of different kinds of trees, such as the different 

 kinds of oak, but seems to do best on the black oak {Quercus tinctoria) 

 and laurel oak {Q. imbricaria), though it will feed also on post oak {Q, 

 obtusiloba) and other species. Found also feeding on hickory, locust, 

 plum, cherry, apple, and peach." (Riley's unpublished notes.) 



The caterpillar. — Pale blue, sprinkled over with black points and dots. Along the 

 middle of the back is a row of ten or eleven oval or diamond-shaped white spots ; be- 

 hind each of these spots is a much smaller white spot, occupying the middle of each 



* Report of the Entomologist, 1885. Ottawa. 



