OSBORN AND BALL STUDIES OF NORTH AMERICAN JASSOIDEA. 85 



Life History: This species appears to be confined to the species of 

 Sporobolus that form mat-like patches of grass, and on these they occur 

 in marvelous abundance. The larvae appear before the middle of May 

 and are similar in appearance to the short-winged females, nearly 

 white when small, becoming a light lemon-yellow by the time they are 

 full grown. From these larvae both long and short- winged adults fol- 

 low before the middle of June. The short-winged forms are the most 

 abundant and remain through July, depositing eggs for the second 

 brood. The long- winged forms only remain a few days on the spot 

 where they issued, but disperse to start new colonies. The second 

 brood of larvae appear in July and become adult in August, remaining 

 through the autumn. The long- winged forms seem to be fewer in fall 

 than in spring. 



This is the most remarkably polymorphic species oi Jas sides that has 

 as yet been found, there being five distinct color variations, and two 

 distinct structural types, these scarcely varying in the hundreds of ex- 

 amples studied. It seems remarkable that so abundant and interesting 

 a species should have remained so long without notice. 



LoNATURA? MEGALOPA u. sp. (Plate IV., Fig. I.) 



Form and general appearance similar to A. artemisioe, but differing 

 in venation, markings and wing length; head bluntly roundingly 

 pointed, yellow, with an interrupted black band before the eyes, pro- 

 notum and elytra grayish-olive, abdomen black with white rings. 

 Length, 3 mm.; width, a little more than i mm. 



Macropterous fortii: Verte.x half the width of head, one-third wider 

 than length on middle, twice wider than against eye, disc convex, 

 sloping, anterior margin broadly rounding to the face, ocelli well over 

 the margin not far from the eyes, face broad and short, front convex 

 in both diameters, gradually narrowing with nearly straight margins to 

 the lorae, then rounding rapidly to the long straight-margined clypeus, 

 suture with clypeus distinct but not depressed, lorae narrow, genae 

 roundingly angled, rather broad below the lorae. Pronotum very little 

 longer than vertex, very broadly rounding in front, twice wider than 

 long, side margins strong, humeral margins rounding. Elytra more 

 than twice longer than wide, overlapping behind with a distinct appen- 

 dix reaching a little beyond tip of abdomen, sub-hyaline with broad 

 light nervures narrowly but distinctly margined with brown, apex with 



[Proc. D. A. N. S., V0L..VII.] II [ January 12, 1898.] 



