Euchalcis vetusta. 293 



some possible clerical error, Dufour, habitually so pre- 

 cise, should have transcribed red for black, and black 

 for red ; nor can it be deemed more plausible that, 

 while carefully recording in his notes the minutest 

 details and specially adverting to the posterior femora, 

 he should have omitted to define their most striking 

 characteristic ! Moreover, to sink the described species 

 to an aberrant qualification would render its diagnosis 

 abortive and illusory. Why, indeed, should not Dufour's 

 E. vetusta, coinciding therewith, occur again on the 

 banks of tlie Ebro ? Has anyone, in France or else- 

 where, reared such a so-called "variety" commingled 

 with others corres[)onding with its ideal representative ? 

 Do we even know that the Spanish specimen was 

 nurtured by the same species of bee ? What then can 

 be held to justify such a transfiguration ; rather than 

 regard Dufour's type — of different origin and unknown 

 life-history, completing also its metamorphoses at an 

 earlier period (March instead of June) — as essentially 

 distinct from the species now inaugurated in its stead ? 



Let us listen, however, to Dufour's arguments in a 

 strictly parallel case recorded in the same Memoire of 

 1861, when, adverting to the C. Dargelasii, confounded 

 by Latreille with the C. rnjipes, Oliv., Dufour remarks : — 

 "Quant a la couleur de ces grosses cuisses d'un rouge 

 ferrugineux qui saute aux yeux, Olivier n^eiit pas manque 

 de la signaler si elle avail existe dans son espece, et il a 

 garde le silence" {loc. cit., p. 10). We have only to read 

 Dufour for Olivier, and the application is perfect. Can 

 we then attribute such palpable inconsistency to the 

 inspired writer of these worcls ? Do they not convey — 

 as it were by anticipation — his indignant protest against 

 such an incredible oversight being imputed to him? 

 What, indeed ! Commit the same blunder himself on the 

 one page, which he repudiates in Olivier on the next ! 

 His attention had been thus forcibly called to the very 

 point now at issue, as regards the presence or the 

 absence of those conspicuous red femora which, according 

 to his own dictum, he could not have failed to indicate 

 in his recorded notes had such existed ; yet, like Olivier, 

 il a garde le silence ! 



But, irrespective of this, I would ask — By what 

 criterion are we to be guided in works of reference, 

 if not by the authoritative descriptions originally sup- 

 plied for this purpose ? Are we, as in this instance, to 



