No. 22.] HYMENOPTERA OF CONNECTICUT. 645 



SPHECOIDEA. 



By Sievert Allen Rohwer. 



The wasps grouped together in the superfamily Sphecoidea 

 resemble bees in that the pronotum is developed on the dorsal 

 lateral margin into rounded lobes called tubercules. These tuber- 

 cules, in some groups, extend beyond the anterior margin of the 

 tegulse, but in no case does the posterior margin of the pronotum 

 touch the tegulse as is the case with the superfamilies Vespoidea, 

 Ichneumonoidea, etcetera, nor is the pronotum large and devel- 

 oped laterally. 



The European authority, F. F. Kohl, has considered these 

 wasps as belonging to one family; but the American authority, 

 W. H. Ashmead, erected a superfamily for the wasps here treated, 

 and recognized a number of families which, in turn, he divided 

 into subfamilies and tribes. The primary character used by 

 Ashmead in separating families of the superfamily was the num- 

 ber of calcaria on the intermediate tibiae. This arrangement 

 separated such closely related groups as Bemhex and Stizns, and 

 also brought together certain other insects which are not, accord- 

 ing to the present author's views, closely related. 



Kohl's treatment of the family did not divide it into subfam- 

 ilies or tribes; but at the end of his classification he arranged 

 genera, subgenera and species in assemblages which he called 

 generic groups. Many of these groups have been raised to 

 either subfamily or tribal importance in the following classifica- 

 tion, and most of the groups Kohl treated as subgenera have 

 been considered as genera, while many of his species groups have 

 been treated as subgenera. 



The other important work on Sphecoidea is that of W. J. Fox. 

 Fox's work, although it does not tabulate all the North American 

 genera and subgenera in the outline of classification, which is 

 according to the older methods, is extremely valuable and reliable, 

 but does not succeed, according to the views of the present author, 

 in establishing a natural classification for these insects. The 



