THE DORYLID^E. 175 



cealed. The male has not yet been noticed, and per- 

 haps not before known, as it differs in this particular 

 from its female. The genus has hitherto been con- 

 sidered wholly American; but we possess a species from 

 New Holland, and we are acquainted with a closely 

 allied genus from the east. It appears to us, from a 

 careful review of an extensive collection of the Formi- 

 cidte, that the genera hitherto established, with a few 

 exceptions only, constitute the types of as many natural 

 families. Contiguous to the Formicid&we observe the 

 Dorylidtf, a small and very natural group of insects, 

 one sex only (the males) of which, throughout its four 

 very distinct and marked forms, have yet come to Eu- 

 rope; and this is the more striking, as the genera con- 

 sist of several species. We have hazarded the hypo- 

 thesis*, founded upon analogous peculiarities of structure 

 both with these and the contiguous groups, that certain 

 blind and apterous insects, ant-like in their appearance, 

 from Africa and the West Indies (Anomma Shkd. and 

 TyphloponeWestS), may possibly be the females of some; 

 but this is merely conjecture. Two forms of this group, 

 Dorylus and Rhogmus, occur in Africa; the former, how- 

 ever, extend to India. The latter continent exhibits 

 another form peculiar to itself ((Eriictus Shkd.), which 

 links, by participating in the structure of both, Dorylus 

 with that form of the group (Labidus) found exclu- 

 sively in America and its dependencies. These insects 

 are further remarkable from the sexual organ of the 

 male exhibiting specific differences. 



(156.) It is perhaps convenient from this point to 

 enter the Sphecides, through the medium of the Mutil- 

 lidce. Although we here observe apterous individuals, 

 we think the circumstance scarcely a link of affinity 

 with the Formicidce ; for, in the MutillidcB, it is the 

 prolific female which is apterous, which is never the 

 case in the former ; and we have already hazarded a 

 doubt if the neuters be positively abortive females. In- 



* See Shuckard's " Monograph of the Dorylidae," June, 1840. 



