THE CANADIAN ENTOMOLOGIST. 295 



N". Illbioensis $ may be distinguished from the female of N. Sayi 

 by the form of the pygidium and the joints of antenna^. All of the speci- 

 mens of N. Sayi ? have the abdomen four-spotted. In all except two 

 specimens oi N.Illinoensis % the abdomen is five-spotted, or six-spotted, 

 when the mark on segment 4 is broken in two. The single specimen of 

 N. parva ? has the abdomen eight-spotted. I separate the $ oi N. 

 lUinoensis from that of A^ Sayi by the joints of antennae. In N. parva 

 $ the scape is stouter, and the ornaments of abdomen are different. 



N. Sayi is closely related to N. Cressotiii, differing mainly in size 

 and colour. 



CLASSIFICATION OF THE FOSSORIAL, PREDACEOUS AND 

 PARASITIC WASPS, OR THE SUPERFAMILY 

 VESPOIDEA. 



BY WILLIAM H. ASHMEAD, ASSISTANT CURATOR, DIVISION OF INSECTS, 



U. S. NATIONAL MUSEUM. 



(Paper No. 3. — Continued from page 188.) 



Subfamily II. — Ageniinse. 



The majority of the species falling in this subfamily are usually 

 smaller and much less conspicuous than those in the other subfamilies, 

 and with totally different habits. None are true diggers, but, on the con- 

 trary, build small oblong, or oval, clay cells, beneath the loose bark of old 

 trees, under stones, or in crevices in old stone walls, etc., not unlike 

 some of the Potter wasps (Eumenid(e). 



The group comes evidently nearest to the Pepsitice, the females 

 having, as in that group, a transverse grooved line, impression or emar- 

 gination on the second ventral segment. From that group, however, it 

 is at once separated by the difference in the legs, the hind tibiae being 

 sm.ooth, never serrate or spinous, or with a longitudinal ridge, but, at the 

 most, with only a few very minute, scarcely perceptible spines. 



These characters readily distinguish the Ageniince from all other 

 Pompilids. 



The beginner at first might possibly confuse some males in this 

 group with some small males belonging in the subfamily Poinpilince, 

 since there is a superficial resemblance in some, but strongly spined legs, 

 always existing in the males of the latter group, ought readily to d'ffcr- 

 entiate the two. 



