232 [September, 



the suggestion thai the two wsisps arc not specifically distinct was made fifty years 

 ago by Schcnck ('53). He considered /'. a«*<rjaea as a mere variety of I', rufa, 

 bearing llie same relationship to the latter as T^. saxonica is believed by many to 

 bear to J', norvegica. This suggestion has lately been revived by Cuthbei-t ('02), 

 who is struck by the constant association of V. austriaca with V. rufa in Ireland. 



During the last few years, however, the opinion has become established that 

 F. austriaca has no workers, but breeds as an inquiline in the nest of some other 

 species. This suggestion as to its habits was first made by Morawitz TGi) and 

 supported by Schmiedeknecht ('81), who, on the ground of its supposed cuckoo- 

 parasitism, proposed a new genus — Pseudovespa — for its reception. Holmgren ('83) 

 stated that on an islet of the Baltic off Stockholm he found J^. austriaca " comme 

 parasite ou invitee chez une congenere V. germanica." We may be pardoned for 

 asking on what evidence this statement rests. But the careful observations of 

 Kobson ('98) have been accepted as showing clearly the inquiline relationship of 

 J^. austriaca to 7'. rufa. 



For ill July, 1887, Robson observed a worker of J'espa rufa dragging from a 

 nest the decapitated and mutilated carcase of a queen T\ austriaca. It was not 

 until ten years later that ho recognised this queen as belonging to the latter species. 

 At the time he considered her to be the dead foundress of the rufa nest, and this 

 opinion he thought well confirmed, when, having taken the nest shortly afterwards, 

 he discovered no old queen within. There were, however, four newly emerged 

 young queens, and in the cells vacated by them fresh eggs had been laid, presumably 

 by some of the workers. In 1897, having determined as V. austriaca the mutilated 

 queen which he had seen dragged out ten years before, Robson made a careful 

 examination of the nest, wliich he had fortunately preserved. In the central cells 

 of the lower of the two layers of comb, he found sis or eight austriaca queens, and 

 in the outer cells of the same layer forty males, whose determination was impossible 

 owing to decay. The circumferential closed cells of the upper layer of comb were 

 tenanted by austriaca males, while rufa males were found in the more internally 

 situated cells. 



From these careful observations, tlien, Robson concluded that the nest must 

 have been founded by a rufa queen (because typical males and workers of that 

 species were found in it), and that the austriaca queen, which he had seen dragged 

 out, liad subsequently invaded the nest as an inquiline " and utilized the energies 

 of the workers of F. rufa in rearing her brood of males and perfect females." 



The capture on the wing of many male and female specimens of Vespa austriaca 

 by one of us, at Fenagh, Co. Carlow, and the discovery, in July, 1902, at the same 

 place of a nest, like that examined by Robson, inhabited by both /'. rufa and 7'. 

 austriaca, has led us to examine afresh the question of the relationship between 

 these two wasps. We have made a somewhat careful comparison between many 

 individuals of the two forms, especially with regard to the armature and face- 

 markings of the males, and the mouth-parts of the females ; and we now publish 

 the main results of our enquiry, together with an account of the nest which was 

 kept for some weeks under observation in a working state. We propose first to 

 recount the facts that we have been able to verify, and then to suggest the explana- 

 tion that seems to us the most probable. 



The characters by which Vespa rufa is usually distinguished from V. austriaca 



