3IO CONNECTICUT GEOL. AND NAT. HIST. SURVEY. [Bull. 



prothorax, and most of fore and mid legs, yellow or yellowish; 

 mandibles and all tarsi more or less brown ; hind coxae and their 

 femora mostly reddish stramineous, the latter tinged with brown- 

 ish above, especially at base and apex ; their proximal trochanters 

 mostly brown, their distal trochanters mostly yellow ; hind tibiae 

 almost entirely concolorous with their tarsi ; wings hyaline, tinted 

 with brown, stigma and veins dark; more or less of the dorsal 

 abdominal segments with a rather obscure apical margin of a 

 yellowish hue; exserted portion of ovipositor about half the 

 length of the abdomen. 



Xylonomus Gravenhorst. 



Key to Species. 

 i. Body either without pale markings or with inconspicuous 



ones -. 2 



Body conspicuously marked with yellow, length 12 mm.; ex- 

 serted portion of ovipositor about as long as abdomen; 

 wings transparent, tinted with brownish; fore and mid 

 legs mostly stramineous, hind legs mostly brown; antennae 

 of female with a yellow annulus near their tips, of male 



apparently uniformly brown albopictus 



2. Almost uniformly blackish or black, legs included, except 

 knees, base of tarsi, an annulus near apex of tarsi and an 

 annulus near middle or at middle of antennae, all of which 

 are more or less yellow; wings darker than in albopictus; 

 length 10-24 mm.; exserted portion of ovipositor about as 

 long as body; antennae of male uniformly dark brown or 



blackish stigmapterus 



Color mostly as in stigmapterus, from which it differs notably 

 in the tegulaa, which are brownish stramineous, in the pale 

 annulus of the female antennae being near the tips of the 

 same, and in the fore and mid legs being almost entirely red- 

 dish stramineous. Length 15 mm. or somewhat shorter 



humeralis 



X. albopictus Cresson. 

 X. stigmapterus Say. 

 X. humeralis Say. 



Xorides Gravenhorst. 

 X. vittifrons Cresson. 



Female: length 15-20 mm.; a rather M-shaped mark below 

 the border along the inner orbits, a mark on the malar space, and 



