( xxxiii ) 



Mr. McLaclilan said he attached great importance to the 

 genitalia as structural characters in determining species, and 

 he believed that he could name almost any species of European 

 Trichoptera simply from an examination of the detached 

 abdomens of the males. 



Mr. Osbert Salviu said he had examined the genitalia of a 

 large number of Hesperida3, with the view of considering their 

 value in distinguishing species, but at present he had not 

 matured his observations. 



Mr. Jacoby, Mr. Bethune-Baker, Colonel Swinhoe, Mr. 

 George Lewis, Dr. Sharp, Mr. G. F. Hampson, and Mr. 

 Champion continued the discussion. 



Mr. S. H. Scudder communicated a paper entitled " New 

 light on the formation of the abdominal pouch in Parnassius.'" 

 Mr. Elwes said he had based his classification of the species of 

 this genus largely on the structure of this abdominal pouch in 

 the female. It had been considered doubtful whether the fluid 

 which formed this pouch was secreted by the female or the 

 male ; but he thought that it was secreted by the latter, as 

 after pairing the male frequently died from exhaustion. He 

 was glad to find that this supposition had been proved by Mr. 

 Scudder to be correct. 



Mr. Jenner Weir remarked that a similar abdominal pouch 

 was to be found in Acrmt, especially in that division of the 

 genus which Doubleday had separated under the name of 

 Hyalites. The pouch was very well developed in the female 

 of Jrli/alites horta, L., and was also found in H. neohule, Doubl., 

 and H. anemnsa, Hewits. It was worthy of remark, as had 

 been pointed out by Mr. Eoland Trimen in his * South African 

 Butterflies,' that Parnassius presents two other characteristic 

 features of Hijalitt's, viz., semi-transparent wings, and simple 

 tarsal claws lobed at the base. 



Mr. Hampson referred to specimens in Mr. Leech's col- 

 lection of a male of one species of Parnassius taken in copula 

 with a female of another species, in which the pouch peculiar 

 to the species to which tlie female belonged had been formed, 

 and, not fitting the claspers of the male, had come away 

 from the female on the specimens being separated, and 

 remained attached to the male. 



