INSECTS INJURING OAK-LEAVES. 159 



with a pale and dark shade, the vascular line dark and broken. Many of these are 

 now crawling about quite actively, while others are in the pupa state and others 

 issuing. They were all in a very slight elastic silken cocoon. 



September 20, 1874 : A number of all sizes on oak, separated into three lots — a in cage 

 12 ; & in cage 10 ; c in cage 5. They are very variable and there are specimens inter- 

 mediate between these three forms. Some have the colors very bright and distinct, 

 and others less so. A lot found on linden, but afterwards feeding well on oak, are all of 

 the light form a in cage 13. 



November 21, 1874: In sieving the cages containing forms a, b, and c, they were 

 found still in the larval state, some having made a tough silken cocoon, others one 

 made only of a few threads, while some had no cocoons at all but had made a smooth 

 cavity in the earth. In cage 5 were found two large Tachina larvte, certainly from 

 form c, one of which is preserved in box 7-40. April 10, 1875, one Tachina fly is- 

 sued marked 359°. One moth issued April 16, 1875, the larva of which was found on 

 linden, but fed also on oak iu cage 13, where there are many more in the ground. 

 Braconid parasite bred October, 1874. October 26, 1875 : Nine from oak all near 

 form b. (Unpublished notes.) 



Full-grown larva — Variety a. — Length, 40™'" (1.50 inches), rather slender, subcylindri- 

 cal. Head pale green with a deep purplish lateral line bordered below with a pure 

 white line; dorsum of abdomen bluish-green with a narrow white dorsal line; the 

 green dorsum is bordered each side by a narrow, scarcely noticeable yellow line run- 

 ning from the head to the fourth segment, from which poiut it is purple to the end of 

 the body; this line is bordered below by a very distinct pure white subdorsal band; 

 the sides are bluish with dark purplish spots ; stigmata orange ; below the stigmata 

 a faint interrupted yellow band ; the dorsal and lateral piliferous warts are yellowish ; 

 subdorsal whitish. The first thoracic segment has two jellow dorsal tubercular spots; 

 segments 2 and 3 have each a yellow dorsal double wart, and the first abdominal 

 segment has two quite conspicuous red piliferous tubercles; the penultimate segment 

 is somewhat gibbous above and bears two small reddish piliferous tubercles. 



Variety h. — Head dark yellow; dorsum of body purplish with paler mottlings; 

 dorsal line white; the subdorsal white line interrupted on abdominal segments 3 and 

 6; the sides rather browner than the dorsum; lateral line yellow and more distinct 

 than in variety a. Stigmata orange ; the first thoracic segment has the yellow tuber- 

 cle, but segments 2 and 3 have only the lower one of the double tubercles yellow. In 

 other points it resembles variety a. 



Variety c. — Head very pale yellow; dorsum pale grayish; dorsal white line bor- 

 dered each side by a narrow purplish line. The subdorsal band consists of. a narrow 

 purple line, an indistinct yellow line, aud a broad white band; the subdorsal lines 

 approximate on the thoracic segments as iu other varieties; the lateral line is yellow, 

 distinct, and uninterrupted; sides slightly darker than the dorsum aud specked with 

 purplish spots. (Conistock, U. S. Ag. Report for 1880.) 



217. Heterocampa pulverea Gvote amA Robinson. 

 Order Lepidoptera ; family Bombycid.e. 



Professor French has reared this caterpillar, which occurred in Union 

 County, 111., .Tune 30 ; July 6 it went into the dirt of the breeding-cage 

 to pupate, the moth appearing August 6. 



The caterpillar. — Length, 1.25 inches [in shape tapering slightly from the middle 

 forward, but more rapidly from that point backward, the body deeper than broad.] 

 General color bright green, head gray, first segment behind the head with two dark 

 purplish-black dorsal warts; from these a purplish-brown line extends backward. 

 This purplish-brown color extends over the hack part of the sixth segment, the whole 

 of the seventh, and most of the eighth. On the third segment begins a dorsal orange- 

 patch,' which reaches back to the sixth segment, filling the space between the p..rple 

 lines. On the ninth segment is another orange-patch. The tenth segment has uo 



