228 The Irish Naturalist. September, 



If the armature of the males of our native wasps be com- 

 pared, there can be no doubt that a very close likeness between 

 Vcspa rufa and V. azistriaca is apparent. The armature in 

 these two species is much more alike than in any other two of 

 our wasps, and it differs from that of the ground-building 

 species {V. vulgaris and V. gamanica) more markedly than 

 from that of the tree-building species ( V. sylvestris and 

 V. uorvegica). Indeed, taking all points of structure into 

 consideration, few entomologists would hesitate to arrange 

 our six Irish species of Vespa into three pains — vulgaris and 

 germanica, rufa and austriaca, sylvestris and noivegica — and to 

 admit that r^ifa and austriaca are much more nearly akin than 

 the two members of either of the other pairs of species. 



Much stress is laid by Robson on a supposed constant 

 difference between the mouth-organs of Vespa rufa and 

 V, austriaca. *' The mandibles [of austriaca^ are," he writes, 

 '' smaller and less rugged, .... and the ligula or tongue 

 is very distinctly smaller than in V. rufa.'' After exami- 

 nation of a number of females of both forms, we can confirm 

 his statement as to a difference in the mandibles (figs. iS, xviii.), 

 but the difference is exceedingly slight, the mandibles of 

 V. 7'ufa resembling those of V. austriaca much more closely 

 than those of any other species. V. vulgaris and V. germaiiica 

 have decidedly larger mandibles than our two forms — 

 V. sylvestris and V. uorvegica decidedly smaller. The state- 

 ment as to the relative length of the tongue is true of some 

 specimens, but in this character a more considerable amount 

 of variation than in others is to be noticed. While the tongue 

 of the female V. rufa is, on the average, longer than that of 

 V. austriaca {^g^. i6, xvi.), some specimens of the former have 

 a tongue no longer than that of some examples of the latter 

 (figs. 17, xvii.). Indeed this character, on which it has been 

 proposed to found a generic distinction, is one of the few in 

 which the two wasps show a complete series of connecting 

 links. 



Our comparison of the structure and markings of these 

 two wasps shows, therefore, that they are distinct forms which 

 do not merge the one into the other. And yet they are more 

 nearly related to each other than either is to any other wasp, 



