No. 22.] HYMENOPTERA OF CONNECTICUT. IO3 



Trichiosoma Leach. 

 Key to Species. 



1. Abdomen black, or at most with only the apex and lateral 



margins more or less rufous 2 



Abdomen entirely rufous, or at most with only first and 

 second segments with bars of black; tibiae and tarsi yel- 

 lowish white; remainder of body black; pubescence of ver- 

 tex black, of front, thorax, and base of abdomen, yellow; 

 abdomen in great part bare, sides of segments with a 

 short yellow pile with scattered longer hairs. Length 

 15-20 mm confusiim 



2. Abdomen wholly black or at least the last segment in most part 



black • • 3 



Abdomen black with apex and lateral margin rufous, at least 

 the apical segment always rufous; tibiae and tarsi yellow; 

 remainder of body black; pubescence of vertex and front 

 woolly, black, mixed with a few yellow hairs; pubescence 

 of thorax and abdomen long, yellow, woplly and matted. 

 Length 20-25 mm triangulum 



3. Abdomen densely covered with short black pile; tibiae and 



tarsi yellow; remainder of body black; pubescence of head 

 and abdomen black; pubescence of thorax yellow, except 

 a transverse band across the middle, which is black; abdomen 



short and broad, broadest at middle. Length 15 mm crassum 



Abdomen covered with long, woolly, gray hair; tibiae and 

 tarsi yellow; tibiae sometimes infuscated at base; remainder 

 of body black; pubescence of entire body consisting of 

 woolly gray hairs, more abundant on head and thorax; 

 abdomen long and slender, sides parallel. Length 15-18 

 mm spicatum 



°T. confusum MacGillivray. 



T. triangulum Kirby. Howard, Insect Book, PI. xii, Fig. 

 5. Larva feeds on willow, wild cherry, poplar, alder. New 

 Haven (F. E. Willits) ; Oxford, 21 May, 1904 (W. E. B.). 



T. crassum W. F. Kirby. Lyme, i May, 1910 (A. B. C). 

 °T. spicatum MacGillivray. 



Cimbex Olivier. 

 Key to Species. 

 I. Tibiae pale yellow; body black, with antennae, tibiae and tarsi 

 yellow; prothorax, middle of abdominal segments two to 

 five and part of following segments yellowish ferruginous; 



