( cc ) 



Mr. Eaton in Algeria — the staining in certain cases of the 

 wings, and also their iridescence, which however could hardly 

 be discussed without consideration of such phenomena in 

 Exotics — and others which I regret my inability to treat 

 satisfactorily, e. g. the chemical and physiological causes 

 determining Colour-characters, which have been studied in 

 Lepidoptera by such experts as Professors Meldola and Poulton 

 and others. 



I will therefore end by offering to the Society my thanks 

 for two years' peaceful enjoyment of a position, not only the 

 most distinguished, but in several ways the most agreeable 

 and interesting, that I have ever occupied, or can ever expect 

 to occupy. I have to thank, also, my fellow-Officers and 

 colleagues in the Council for all that they have said and 

 done to encourage and assist me in discharging duties not 

 indeed actually onerous, but at any rate responsible ; and, 

 finally, to welcome with sincere congratulations and good 

 wishes our able and popular colleague, Mr. Bethune-Baker, to 

 whom I now resign this Chair. 



NOTES. 



A. Mr. Waterhouse, since the above was written, has called my atten- 

 tion to the Mymaridae, where the S antenna has generally several more 

 joints than the 9 ; (often 13 as against 9 !). See p. clxxxi. 



B. Dr. T. A. Chapman has seen the S Odynerus spinipes "imprison 

 the wings of the 9 " between his (tridentate) middle femora, and (excavated) 

 middle tibiae. E. M. M. 1870, p. 214. See p. clxxxiv. 



