( Ix ) 



"This large dominant Coloiu-gronp is not only exemplified 

 by Odynerus moutanus, but also by four other species, each of 

 which represents a quite different Structure-group, and if 

 there was any good classification of the heterogeneous mass 

 forms called Odynerus, each would, in my opinion, repre- 

 sent a distinct genus. In addition to these and many otlier 

 species the group contains Nesodynerus rudolphl and others, 

 Pseudopterocheihis comjrims and others, Chelodynerus clielifer, 

 Perkins (not sent to you), various species of the three 

 Fossorial genera, and of the Anthophilous genus Neso2)rosopis 

 — consequently representatives of nearly all the existing 

 Hymenoptera of the Hawaiian islands. 



" Hawaii appears to be tending to total blackness, owing to 

 the predominance of this single Colour-group, the red of the 

 red forms becoming duller or diminished, the bauds of the 

 banded forms more or less obsolete." 



Prof. PouLTON said that he had but few comments to make 

 on Dr. Perkins's interesting and valuable paper, and, in fact, 

 he felt considerable diffidence in making any suggestions at 

 all on the work and conclusions of such a master of the 

 Hawaiian fauna as the author had proved himself to be. 

 Nevertheless he ventured to make a few remarks bearing 

 upon the origin and present distribution of the Colour-groups 

 in the islands and on one or two other points. Dr. Perkins 

 had brought forward strong evidence for the conclusion that 

 the first immigrant Odyiienos was an ordinary-looking yellow- 

 banded species — viz. one that had previously been an insigni- 

 ficant member of one of the largest and most widely dis- 

 tributed of the Aculeate combinations, containing many of 

 the most formidable and dominant species, and bearing pro- 

 bably the simplest and most effective of warning patterns. 

 The immigrant ancestor had behind it endless generations in 

 the course of which its pattern had been rendered stable by 

 selection ceaselessly exercised on some unknown contineiital 

 area. Thus it was possible to understand the remarkable fact 

 that so much of the original pattern should have survived or 

 should still be revealed by reversion, at the close of a period 

 long enough to have produced all the Eumenid Structure- 

 groups in the islands except that associated with the later 



