ABT.21. NORTH AMERICAN SAWFLY LARVAE — MIDDLETON. 25 



have 4 joints and an apical claw ; the prothorax with A, D, and post- 

 epipleurite bare; B, C, preepipleurite, prehypopleurite, posthypo- 

 pleurite and leg joints sparsely haired ; mesothorax with D and post- 

 epipleurite bare; A, B, and C, alar area, preepipleurite, prehypo- 

 pleurite, posthypopleurite, and leg joints, sparsely haired ; the meta- 

 thorax same as the mesothorax. Abdomen: The tergum of urites 

 1-9 is composed of areas A, B, C, and D (C inclined to subdivide 

 Qi-2-3^^ A and D are bare, B and C are sparsely haired and urite 10 

 consists tergally of an epiproct which is sparsely haired and without 

 pseudocerci; urites 1-8, inclusive, with spiracle in a rather well- 

 defined spiracular area and the alar area is bilobed and sparsely haired, 

 urite 9 with the spiracle and spiracular area wanting and the alar 

 area wanting or not distinct and urite 10 with spiracle, spiracular 

 area and alar area wanting; in the pleurum; urites 2-7, inclusive, 

 with preepipleurite, postepipleurite, hypopleurite, and uropods, 

 urites 1 and 8 with a rather distinct preepipleurite but with indis- 

 tinct postepipleurite and hypopleurite and no uropods, urite 9 with 

 the pleurum indistinct and no uropods, and urite 10 pleurum indis- 

 tinct, postpedes present and with postcallus not very prominent; 

 urites 1-9, preepipleurite, postepipleurite, and uropods sparsely 

 haired, urite 10 postpedes sparsely haired and the postcallus rather 

 thickly haired. 



Color. — Head: Leaf green with few dusky marks. Body: Leaf 

 green. 



Cocoon. — 9 mm.' long by 3.5 mm. in diameter; thin, single-walled, 

 medium texture, capsule-shaped or elliptical in outline with one or 

 more flattened surfaces due to contact. Blackish brown in color. 



Host. — Betula alba Linnaeus. 



Remarks. — Described from material collected August 23, 1915, at 

 East Eiver, Connecticut, by C. R. Ely and recorded under Hopk. 

 U. S. number 10757^. All the larvae had shed becoming prepupae 

 and spun their cocoons by September 10, 1915, and adults emerged in 

 the cage on May 17 of the following year. 



Genus PONTANIA Costa. 



PONTANIA AMENTIVORA Rohwer. 



Oviposition. — Oviposition occurs about the middle of April when 

 the pistillate catkins are about half grown. The adults (observa- 

 tions from reared specimens in captivity) prefer, apparently, the 

 medium and slightly developed catkins. Oviposition, in the large 

 majority of cases, occurs at the tip of the bud. (Those exceptions 

 observed are cases where large, nearly full developed buds are at- 

 tacked; here oviposition is made at the basal swelling of the bud.) 

 So far as could be observed the adults did not feel over a particular 



