( xcvii ) 



between the under-side of the wet-season phase of Teracolus 

 regina and that of certain forms of Belenois from the same 

 region of Africa — a resemblance believed by the exhibitor to 

 be of mimetic significance. He pointed out that between B. 

 calypso and B. thysa, which latter was an acknowledged mimic 

 of the distasteful Mylothris agathina, there existed a fairly 

 complete series of transitional forms, one of which at least 

 showed on the under-side a striking resemblance to the under- 

 side of the wet-season T. rejina. It seemed as if M. agathina 

 had exercised a strong influence on this group of Belenois, and 

 that in the progress of these Belenois-iovvas towards the 

 final mimetic pattern shown by B. thysa, one of them had, as 

 it were, taken up T. regina in its course. The association 

 between the Belenois and the Teracolus was probably Mlillerian, 

 the Belenois being in most respects the model ; but it was 

 pei'haps not improbable that the Teracolus had to some extent 

 influenced the Belenois. These specimens seemed to favour the 

 view that B. thysa was a Mlillerian rather than a Batesian mimic. 

 It was an interesting fact that the cryptic character of the dry- 

 season form, as well as the mimetic appeai'ance of the wet-season 

 phase of the Teracolus, was confined to the under surface ; 

 being presumably in both instances intended for use during 

 rest rather than in flight. As in other cases, the dry-season 

 form was probably the more efiiciently protected. It might be 

 taken as a general rule that in cases of seasonal dimorphism, 

 if one phase only were protected, that phase would be the 

 dry-season one ; if both adopted means of defence differing in 

 degree or in kind, the dry-season phase would be the better 

 protected of the two. 



Mr. W. J. Lucas showed on behalf of Messrs. H. and F. 

 Campion a male specimen of Symipetrum vulgatum taken in 

 Epping Forest on the 4th September last. The only other 

 authentic British specimens are : (1) a male in the collection 

 of Mr. C. A. Briggs, taken at Bookham Common in 1891 ; 

 (2) a male in his own collection taken 11th Septembei", 1898, 

 in Richmond Park ; and (3) a male taken by Mr. A. H. Hamm 

 at Torquay, 15th August, 1899, which he cannot now trace; 

 but it was carefully examined at the time by the late Mr. 

 McLachlan. Dr. Hagen mentions in the "Entomologist's 



PROC. ENT. 80C. LOND., IV. 1906. G 



