ODYNERUS. 361 



is sufficient to distinguish them ; it is even so striking that one 

 would be tempted to raise it to a genus, did there not exist, 

 principally in Europe and in Africa, a series of intermediate 

 types which allies them by very gradual and natural transitions 

 to the true Odyneri. These transitions are even so complete 

 that one is much perplexed to know how to limit the subgenus 

 Epiponus. 1 But as the intermediate types are principally inhabi- 

 tants of the old world, the difficulty with the American species is 

 much diminished, although it appears in the case of some Ante- 

 piponus. 



The Epiponus seem to be peculiar to the boreal hemisphere and 

 to Africa; the true Epiponus are the northern type, the Ante- 

 piponus the southern type, as well in America as in Europe. 



Division ANTEPIPONUS. 

 (Sauss. Et. Vespid., 111,244.) 



Mandibles of the males not notched, nor armed with a spur. 

 Antennae of the males either armed with a hook, or curled 

 up into a spiral at the extremity. First abdominal segment 

 cup-shaped, sessile or rather subpedunculate at base. As 

 said above, I at first placed this division in the subgenus 

 Odynerus, but the appearance of its representatives being 

 quite that of the Epiponus, it will better find Us place in 

 this division. 



1. Antennas of the males terminated by a hook. (Sauss. Vesp., 



I, 213, Sect. C.) 



No representative yet found in America. 



2. Antennas terminated by a spiral curl. (Sauss. Vesp., I, 216, 



Sect. IP.) 



This section only differs from the true Epiponusby the mandi- 

 bles of the males being simple, and the clypeus not so much 



1 In my Etudes sur hx Fam. des Vespides, I have inoluded those transitory 

 species in the division Anteptpona (HI, 298), but this division is only 

 an expedient to help in the determination of the Speoies ; it is not a 

 natural division— no more than any section one must form in a continu- 

 ous series, conducting from one form to another by gradual transitions, 

 (Couip. Et. Vespid., Vol. I, 213, C, and 216, II. — Ibid!. Vol. 111. 298.) 



