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tufts were passed to and fro over the surface of the brands 

 as though some secretion was being conveyed from the odo 

 to the other. Prof. Poulton has suggested that the greasy- 

 appearance of the brands may be probably interpreted on the 

 hypothesis that they serve to retain and distribute a scent 

 employed in courtship brought to them by the tufts." 



Dr. Longstaff said that he was satisfied that in Eiiploea 

 and Danaida chrysippus the characteristic scent was not caused 

 by the tufts and brands, though these were very likely the 

 cause of another volatile scent which certainly existed in these 

 cases. Female Danaids have a scent as well as males ; the 

 scent common to both being nauseous, while that peculiar to 

 the male is probably a help in courtship. 



Prof. Poultox remarked that the brands actually are greasy, 

 and not merely look so, and that they may for a time hold 

 the scent transferred to them by the tufts. 



Dr. Jordan observed that the discovery in Natal of inter- 

 mediates between cenea and planemoides, which from previous 

 experience had been supposed not to exist, made it impossible 

 any longer to argue from their non-existence in favour of the 

 sudden, as opposed to the gradual, evolution of dimorphic 

 forms. 



Wednesday, October 4th, 1911. [liii 



Separation of tiie Sexes in Hypolimnas misippus.— 

 Dr. F. A. Dixey read a letter received by him from Mr. 

 E. A. Agar, of Dominica, West Indies, on the subject of 

 the Separation of the Sexes of Hypolimnas misippus, in which 

 the writer remarked that in that island, although haunting 

 similar localities, the $ remains on the coast while the £ is 

 to be met with some distance inland. The former is scarcely 

 ever to be seen in company with the $ of its own species, 

 though it flies with Danaida plexippus, of which it is a mimic. 

 Mr. Agar suggested that it looked as if " both sexes were 

 aware that if they flew in close association it would give 

 the show away," which implies intelligence of too high an 

 order. 



Dr. Dixey remarked that it was a common experience that 



M 



