184 MODERN CLASSIFICATION OF INSECTS. 
micarie and Mutillaria into a third subsection, named Heterogyna 
(from the apterous condition of some of the individuals), placed at 
the head of the section; and the Vespide intoa fourth, named Diplo- 
ptera (from the folded fore wings), immediately preceding the bees. 
With Mr. MacLeay, I can, however, scarcely think the folding of the 
wings in the wasps to be a character of sufficient importance to war- 
rant the establishment of a distinct subsection equivalent with the 
others. 
The subsection Pr#pones has been divided by Latreille into three 
groups: namely, 1. the Fossores Latr. ; 2. the Heterogyna (including 
the Mutillide and Formicide) ; and 3. the Diploptera, or wasps. The 
term Fossores, employed for the first group, is not, however, sufficiently 
precise, since many of the bees and wasps are equally fossorial. I 
would, therefore, propose in its stead that of Insectivora, as all the 
species feed in the larva state upon other insects. The Heterogyna 
ought to be restricted to the ants; the apterous condition of the fe- 
male Mutillide, which are in all respects Fossores, not being suffi- 
cient to warrant their introduction in the same group as the ants ; for 
which, as the females are winged, it will be necessary to employ 
another name. I therefore divide the Pradones into the three follow- 
ing groups : 
1. Insectivora. Fore wings not folded. Larve solitary, feeding on 
other insects. (Linn. gen. Sphex and Mutilla.) 
2. Sodales. Fore wings not folded. Larve social. (Linn. gen. 
Formica.) : 
3. Diploptera. Fore wings folded. Larve, in the social species, 
separately enclosed in cells. (Linn. gen. Vespa.) 
The natural arrangement of these groups is, however, very difficult. 
Latreille, in his late works, has placed Formica at the head of the 
Aculeata, with which is arranged Mutilla, followed by the Fossores; 
commencing the latter with the Scoliida, and terminating with the 
Crabronidee, passing by some of the latter (as Cerceris) and the un- 
folded-winged wasp-genus Ceramius AZ., to the solitary wasps. In 
his Genera Crustaceorum, &§¢., he, however, placed the ants, wasps, 
and bees in juxtaposition ; a step which appears to me to be so ad- 
vantageous that I have adopted it in the following pages.* 
* The consideration that the Newropterous Termitide agree in so many particulars 
with these Hymenopterous groups, is a strong argument against the adoption of the 
