ART. 21. NORTH AMERICAN SAWFLY LARVAE MIDDLETON. 21 



with pieepipleiirite rather distinct from postepipleurite both hirge 

 and sparse!}^ haired, iirite 9 with preepipleurite and postepipleurite 

 forming epipleurite and not distinctly separated and sparsely haired ; 

 urite 10 with epipleurite not recognizable; urites 2-7, inclusive, with 

 hypopleurite distinct, not subdivided into prehypopleurite and post- 

 hypopleurite and not haired and urites 1. 8, 9, and 10 with hypo 

 pleurite indistinct or wanting; urites 2-7, inclusive, with w^ell-devel- 

 oped uropods, urites 1, 8, and 9 with uropods wanting, and urite 10 

 with postpedes and with a rather prominent, thickly haired post- 

 callus. 



Color.— Head: Brownish black, membranes pale, eye disks deep 

 black. Thorax: Prothorax paie, excepting grayish markings ol 

 postepipleurite and posthypopleurite ; neck plates, leg joints, and 

 prehypopleurite brownish black ; mesothorax pale with brownish mid- 

 dorsal line and brownish black laterodorsal spots on A, B, C, and D; 

 alar area with supraalar and alar blackish spots; preepipleurite, 

 postepipleurite, prehypopleurite, posthypopleurite, ana leg joints, 

 blackish; metathorax similar to mesothorax. Abdomen: Urite 1 

 pale with middorsal and laterodorsal brownish black spots on A, B, 

 C, and D; supraalar spots on B and the alar area; alar spots on A 

 and the alar area; epipleural spot on preepipleurite and a pleural 

 spot on postepipleurite; urites 2-7, inclusive, similar to urite 1, but 

 further possessing a lateroventral spot on hypopleurum; urite 8 

 similar to those preceding, but with spots fainter and occasionally 

 several wanting; hypopleurite not distinct but lateroventral spot 

 present, however; urite 9 mostly pale, excepting the alar area and 

 epipleurite and urite 10 pale with the epiproct blackish posteriorly. 



Cocoon. — 9 mm. long by 4 mm. broad; single-walled, close woven, 

 capsule-shaped structure ; brownish black in color. 



Host. — /Salix, species. 



Parasites. — Masicera^ species (determined by C. T. Greene). 



Remarks. — Described from material collected September 23, 1913, 

 at Harrisburg, Pennsylvania, by A. B. Champlain and recorded 

 under Hopk. IT. S. number 11398''. All had become prepupae, gone 

 into ground and spun cocoons by October 28, 1913. On May 26. the 

 following year, an adult diptera emerged in cage. Adult sawflies 

 began emerging on July 24, 1914, and continued to issue until August 

 3, 1914. 



PTERONIDEA PLESIA Rohwcr. 



Like P. mendicana but with postepipleurite pale on prothorax, 

 mesothorax, and metathorax. 



L(Arva. — Stage VI. 



Structure. — Head: As P. mendicana. Thorax: As P. mendicana. 

 Abdomen : As P. mendicana. 



