1903- Carpkntkr & Bkre:sford. — Vespa austriaca & V- rufa. 227 



here also there is some amount of variation (compare 

 figs. 14, 15 with figs, xiv., XV.). We notice that the black 

 markings of the abdominal segments are relativel)^ broader 

 and more truncated in V, austriaca than in V. imfa 

 (figs. 12, 13, and xii., xiii.), but we possess queens of either 

 form showing the abdominal markings of the shape 

 characteristic of the other. In the typical vSpecimens of 

 V. austriaca, the black abdominal markings stand out clear 

 and sharp on the lemon-3^ellow ground ; but full}^ 25 per cent, 

 of the males of this wasp examined by us show a decided 

 rufous tinge around the black, and in some this is so marked 

 that an examination of the shins or the male armature is 

 necessary before the specimen can be satisfactorily deter- 

 mined. On the other hand, some specimens of V. rufa show 

 hardly any trace of the rufous tinge. 



It is believed by most students of the Hymenoptera that 

 the male armature furnishes characters exceptionally reliable 

 for the discrimination of species. In V. austriaca the 

 appearance of the organs generally is narrower, more parallel* 

 sided, and paler than in V, rtcfa (figs. 6, vi.), as was remarked 

 by Robson ('98). I.ooking at the details of the armature, we 

 find that there is a fairl}^ constant difference in the form of 

 the stipes (fig. 6, vi., st.)^ and that the appendage at its tip is 

 narrow in V. rufa, ending in a very slender flexible point 

 (fig. 6, b, fig. 8), but broad and prominent in V. austriaca 

 ending in a straight and more rigid point (fig. vi., b, fig. viii.). 

 But in this character, again, there is occasionally a tendency 

 in each species to vary towards the other (compare figs. 

 9 and 10 with figs ix. and x.). And it is of special interest 

 to find that this variation in the armature sometimes (not by 

 any means always) accompanies the variation in the face- 

 markings. Figs. 3 and 9 have been drawn from one aberrant 

 male of V. rtcfa, figs. 4 and 10 from another; figs. iii. and ix. 

 from one aberrant male of V. austriaca, figs. v. and x. from 

 another. A detail of the armature which seems fairly con- 

 stant is the process on the inner face of the stipes ; this is 

 longer and narrower in V. rufa than in V. austriaca 

 (figs. 6, a, vi., «, 7, vii.), and exhibits very little variation in 

 either form. 



