a Family of the Hymenoptera Heterogyna. 189 



its metropolis. Our present knowledge of the range of the genus 

 Lahidus is of much more limited extent : it has hitherto been found 

 only in the intertropical portion of the New World. As confusion 

 attends the nomenclature of the species hitherto recorded, and 

 wherein evidently several have been included, it will perhaps repay 

 the trouble of investigation to subject them to a critical examination, 

 for thus only will it be possible to extricate them from the disorder 

 into which they have fallen. This has, I have no doubt, arisen from 

 their great rarity, as probably not more than a single specimen, or 

 perhaps specimens of a single species, have been at the time in the 

 possession of either of the several describers, who have all attributed 

 it to that originally published, never more than doubtfully surmising 

 the possible existence of any but that one species ; and so fully pre- 

 occupied must they have been with this idea, otherwise the disparity 

 of the descriptions would have evinced at once that they belonged 

 to different insects. 



The situation which these genera occupy in the system, and their 

 right to form a separate family, has been latterly subjected to discus- 

 sion by very competent individuals — le Comte de St. Fargeau in 

 France, and Mr. Haliday in our own country, who both seem dis- 

 posed to unite them permanently with the social Heterogyna or Ants, 

 and these views they have supported by many arguments. It is 

 however only latterly that they have been separated from the Mutil- 

 lidse, and by these same gentlemen, although less definitely and di- 

 stinctly by St. Fargeau, who calls them Genera provisionally ap- 

 proximated to the Heterogyna *. But Mr. Haliday has first raised 

 them to a family equivalent to the whole of the social Ants, and 

 which with them constitute his tribe Heterogynaf, and he at the 



* It is by this author in the same work, ' Hist. Nat. des Insect.' Hymen, 

 (and in which he is followed by Mr. Haliday), that the term Heterogyna was 

 restricted exclusively to the Social Ants. Latreille comprised within it the 

 MutillidcB also, and it thus consequently embraced all the aculeate Hyme- 

 noptera with apterous females. If the distribution thus introduced is to 

 hold, and they are to be subdivided, and each division to be considered equi- 

 valent to the other tribes, the name Heterogyna ought to remain with what 

 we now understand by the Mutillidce, as it is only these that have anoma- 

 lous females, this sex in the tribe of Ants, as far as they are yet known, 

 being all winged like their males ; the term therefore in application to them 

 is very inappropriate, unless in reference to other sexual discrepancies, and 

 then it could be as legitimately applied to many other Hymenoptera. 1 shall 

 have occasion shortly to go more particularly into this subject, and shall 

 then discuss the propriety of the present contents and distribution of the 

 whole of Latreille's Heterogyna and the neighbouring groups, 



f Dr. Leach had previously formed them into a family by the name 

 Dorylid<B, which he incorporated with the tribe Mutillarides, and he made 

 them equivalent to the whole of the remainder of the MutillidcB, 



