18 Journal New York Entomological Societv. [Voi. v. 



ON THE LARViE OF CERTAIN SAW-FLIES 

 (TENTHREDINIDiE.) 



Bv Harrlson G. Dvar, Ph. D. 



Trichiosoma crassum Kir by. 



L Mr. MacGillivray has sorted out my bred material into two species 



of Trichiosoma, T. triangiilinn and T. crassum. There was no corre- 

 sponding difference in the larv£e, however, and, therefore, that of T. 

 crassion may be described as being indistinguishable from that of T. 

 trianguliim. (See Ent. News, vi, 199.) 



Food-plants. — Willow, poplar, wild cherry and alder. 



Hylotoma scapularis King. 



The flies mentioned in Can. Ent., xxvii, 344, under label 2B were 

 pronounced by Mr. MacGillivray to be males of this species. The fol- 

 lowing is the present state of this confusing subject : 



Larva; head black or red. 

 No paler subdorsal line. 



Tubercles distinctly black. 



Head red, body yellow; on l)irch V. 



Head black, rarely reddish, body yellow ; on wild cherry S. 



Tubercles blackish only, or pale in black rings. 



Head blue black, body yellow •, on oak 2B 



A pale yellow subdorsal line. 



Head red or black, body greenish-yellow ; on willow 2C 



Head pale testaceous with vertical dark band. 



Body green, tubercles nearly all pale 2L 



Here are five rather distinct types of larvre. From V have been 

 bred H. pectoralis, H. scapularis 9 and H. atruleiis $ ; from S has 

 been bred H. mcleayi; from 2^ H. scapularis $ \ larvae 2C were bred 

 from eggs laid by a female H. clavicornis ; 2L produces H. mcleayi $ 

 and H. virescens (^clavicornis') $ . 



Description of larvae 2B. Four last stages observed with widths of 

 head .8, i.i, 1.8 and 2.5 mm. Head rounded, uniform blue-black, 

 the sutures scarcely visible ; small black set^e in front. Body cylindri- 

 cal, subventral ridge prominent ; thoracic feet large, pale yellowish 

 brown, the large basal joint blue-black. Abdominal feet on joints 6 to 

 ID and 13 small, the last pair rudimentary, pale at tip, their bases dotted 

 with black. Segments coarsely 3-annulated with nine large (.35 mm.) 

 setiferous tubercles in an approximate square, the lower posterior one 

 moved inward ; another behind the spiracle ; these tubercles are black- 



