PLATE XX. 
MONOGRAPH OF THE HYMENOPTEROUS GROUP, DORYLIDES. 
——_e—_ 
Tue group Dorylides, composed of the four genera Dorylus, 
Rhogmus, Labidus, and Afnictus, presents to us a series of insects, 
now of considerable extent, of which we still remain in entire 
ignorance of the females, as well as of the natural habits of the 
group; our knowledge being at present confined to the characters 
of the male sex, and to the facts that the males are often 
captured flying by night, and are so rare that out of a dozen species 
of Labidus collected in Brazil, by W. Burchell, Esq., single 
individuals were only found of nearly every species. Mr. Shuckard, 
in his Monograph upon this family, has suggested that my genus 
Typhlopone is composed of the females of Labidus, and has conse- 
quently removed Typhlopone from the family of the ants, in which, 
as [have endeavoured to prove in a memoir subsequently published 
in the Annals of Natural History, he appears to me to have violated 
nature, Typhlopone possessing a far greater majority of the 
characters of the Formicide than of any other family. Latreille 
considered the Dorylides as aberrant Mutillidee, deeming them to 
be solitary insects ; whilst St.-Fargeau and Haliday place them in 
the family of the social ants ; Shuckard however considers them as 
an oscillant family between the Mutillidee and Formicidz, on account 
of their possessing—firstly, only a single recurrent vein to the fore 
wings; secondly, a single calcar to all the tibiee (characters of 
the Formicide) ; thirdly, a labrum closely shutting the mouth (a 
character of both families) ; fourthly, the curtailed structure of the 
palpi (whieh is stated to ‘separate them peculiarly from both 
tribes”); and fifthly, the enormous size of the male genital organ, 
in which Mr. Shuckard states they exclusively resemble several of 
the solitary Heterogyna. The curtailed structure of the palpi and 
the large size of the male genital organ are, however, characters of 
some of the Formicide, as particularised in my observations on 
Typhlopone, and thus in every one of these characters the Dorylides 
are seen to resemble the Formicidee, with which they also agree in 
