OSBORN AND BALL STUDIES OF NORTH AMERICAN JASSOIDEA. 71 



Life History: The adults pass the winter under the leaves and rub- 

 bish in the woods, becoming active quite early in the spring. Some 

 eggs were deposited before the middle of May and from then on nearly 

 through the month. The first larvae were found the last week in May, 

 when a number hatched in the cases and a few were found in the field, 

 the majority not appearing until in June, the egg stage lasting nearly 

 three weeks in the breeding cage where the temperature was fairly 

 constant, probably a little longer under the changeable spring weather 

 out-of-doors. The larvae burst through the projecting top of the egg 

 and are quite active from the start. When first hatched they are 

 nearly white except for their red eyes; the head is nearly twice the 

 breadth of the body. Within a few days they become greenish in 

 color and their body is much larger proportionately. The larvae are 

 abundant throughout June and well into July, the adults beginning to 

 issue the first week, and from then on through the month, remaining 

 abundant through August. The second brood was not as closely 

 watched. The larvae appeared early in September and the adults soon 

 after, remaining abundant until cold weather sent them under cover. 



Idiocerus monilifer^ n. sp. (Plate IIL, Fig. 2.) 



Form of brunneus nearly, more slender behind, resembling alter- 

 natiis in appearance but lacking the fulvous shade and the dorsal white 

 mark. Length, 5.50 mm.; width across eyes, 2 mm. 



Vertex broad, shorter than the eyes ; face convex ; front less pro- 

 duced than in brun7ieiis ; narrow below; clypeus small at the base, 

 much broadened on the truncate or slightly concave apex; genae nar- 

 row, the margins concave, slightly reflexed below. Pronotum broad, 

 disc nearly flat, humeral margin short, nearly straight, anterior margin 

 broadly rounded. Elytra rather long, venation as in alternatus, outer 

 antea]jical cell long, parallel-margined, appendix broad, closely folded 

 posteriorly wlien at rest. 



Color : Vertex yellow, brownish fuscous between the usual black 

 spots which are rather small, a median light line broadest at the base ; 

 face yellow, black above, omitting a yellow spot just outside the 

 ocelli, and another above the antennae ; front yellow with a brownish 

 circle above connected with an oval below ; pronotum nearly irrorate 

 with brownish fuscous on the disc, margins and a broad median stripe 

 light ; scutellum yellow, a spot within the basal angle black, a narrow 

 median line forking at the suture, and two spots on the disc reddish- 



