OSBORN AND BALL —STUDIES OF NORTH AMERICAN JASSOIDEA. 73 



Larvae very distinct, yellowish and reddish-brown, forms with stout 

 bodies and broad roundingly transverse heads, the whole upper sur- 

 face clothed with long coarse hairs. The abdomen is rather broad for 

 this genus and there are about twelve hair-bearing tubercles in a row 

 near the posterior margin of each segment. 



Color: Head yellow, brownish in front ; pronotum yellow, behind 

 which there is a brown cloud and the margins ot the abdomen are 

 brown, broadest in the middle, the disc yellow. 



Genitalia: $, ultimate segment about half longer than the penulti- 

 mate, posterior margin broadly roundingly produced on the middle 

 half, with an obtuse median notch, pygofers short, less than half longer 

 than their width at base. cJ^, valve long, posterior margin produced 

 in an acute median tooth, plates short, stout, curved upward. 



The cinnamon color and the simpler elytral venation render this a 

 very distinct species in our fauna. It occurs abundantly on willows 

 at Ames, and has been received from Nebraska. There are two 

 broods in a season, one in July and the other in September, the latter 

 hibernating and depositing eggs in the spring, which hatch out by the 

 first of June. 



Idiocerus maculipennis Fitch. (Plate II., Fig. 4.) 



This is a very bright chestnut-brown species with light markings; 

 the head is very short and the eyes curve around the pronotum and 

 do not stand out as in the willow species. The face is light-yellow 

 with a red stripe down the middle and two large black spots on the 

 side above. There is a light spot on the pronotum, a v-shaped mark 

 on the scutellum and another of the same color on the wings ; the 

 outer margins of the wings are very dark except for a white patch be- 

 fore the tip. 



The larvae are dark reddish-brown, sometimes blackish in color with 

 broad, blunt heads and prominent eyes. They are very active and 

 though readily seen, are very difficult to capture, dodging around a 

 limb whenever approached. 



They occur very commonly on hawthorn and crab apple trees, the 

 larvae appearing in May. The earlier ones mature by the middle of 

 June and the last early in July; the adults common the latter half of 

 June and nearly through July. The adults were again common the 

 last of August and early in September. 



