12 PROCEEDINGS OF THE NATIONAL MUSEUM vol.75 



Tenth abdominal segment (fig. 60). — ^With six pear-shaped lobes 

 radiating I'rom anus in the middle of the sucking surface. Each 

 side with a slightly chitinized and setae bearing plate. 



Leg (fig. 62). — Coxa, trochanter, femur, and tibia brown with 

 distal end blackish, claw blackish brown. Tibia rather short, some- 

 wdiat contracted and bent medianly. 



II ah its. — Feeding on the leaves especially of red elm, also recorded 

 from hazel {Goryhis am-ericanus) , skeletonizing one leaf after an- 

 other; feeding when in first and second stages on the underside but 

 in the third stage indiscriminately on either side, usually refusing 

 to touch the epidermis of the opposite side but sometimes eating 

 holes through the leaves. Pupates in the ground in a simple oval 

 cavity, a few inches below the surface. 



Literature. — 



Riley, C. V. 



1879. " Repoi't of Commissioner of Agriculture for the year 1878," pp. 

 245-277, pi. 4, figs, a-li (Reprint in "Author's Edition" from Annual 

 Report of Dept. of Agr. 1878. Charles V. Riley. August 1879, pp. 40-42) . 

 Howard, L. O. 



1905. U. S. Dept. Agr. ; Bull. 54, pp. 81-82. 



TRIRHABDA CANADENSIS Kirby 



(U. S. Nat. Mus. ; described from larva in vial marked " North East, 

 Pennsylvania, 1919. E. M. Craighead coll." Reared. 



Mature larva (fig. 3). — About 12 mm. long. 



Head (fig. 37) smooth, varying in color from brownish, in some 

 specimens brownish with black specks, to deep bluish black; labrum 

 shining black; anterior corners of frons light, frontal sutures whit- 

 ish, sagittal line above carina of frons black. Body varying in color 

 from dull brown to indigo-blue ; prothoracic shield uniformly irides- 

 cent dark with light median suture; pygidial shield and dorsal and 

 lateral sclerites transversely striate, with indistinct margins gradually 

 blending into the similarly colored, dark and iridescent skin ; under- 

 side of body cream colored with thin but distinctly colored ochreous 

 sclerites. Legs u.sually blackish brown with ochreous inner side.^° 



Setae whitish, thin, pointed, easily broken, about half, or less, as 

 long as the length of a body segment, present in moderate numbers. 



Head capsule (fig. 37). — On each side close to the epistomal margin 

 and near to the sagittal line with an irregular depressed area bear- 

 ing two setae. 



Labrum. — Subrectangular, about tAvice as wide as long, with front 

 margin slightly emarginate medianly. Discal setae thin, not fully 

 as long as labrum ; marginal setae short and fine. 



1" Larva In first stage unlfornrly brownish, rather glossy, with setae somewhat longer 

 than each body segment. 



