676 Dr. T. A. Chapman on a European Lycaena. 



(marked 2) in thersites, making it nearer to 2 than the second 

 post-discal spot (marked 3) is. The reverse being the case in icarus. 

 Magnified. It shows also the different alignment of the tornal 

 members of the post-discal series of spots. Photo by A. E. Tonge. 



Explanation of Plate LXXXII. 



Showing scales and androconia of 1. thersites, 2. icarus, from 

 identical spots (costal to base of vein 6, forewing) in each species 

 X 300. Photo by F. N. Clark. 



Explanation of Plate LXXXIII. 



Androconia of 1. thersites, and 2. icarus, showing differences of 

 size, shape and ribbing x 500. 



Explanation of Plate LXXXIV. 



Showing terminal segments of abdomen of 1. thersites $ ^nd 

 2. icarus 5 ^ 25 and the differences in the curious eversible 

 structure with a chitinous termination in thersites, which is hardly 

 represented in icariis. 



The everted ventral organ is not fully stretched in either specimen. 

 In L the view is exactly lateral for the basal half, so that the two 

 chitinous areas are superposed ; in 2. the view is ventral, showing 

 both areas. In neither is it fully extended. The terminal half 

 being still slightly sheathed in the first and the end of the chitinous 

 loop is still doubled back. This does not prevent it being obvious 

 that the whole basal process is larger, wider and more chitinised in 

 icarus than in thersites, and that in the terminal half thersites is much 

 narrower and more slender than is icarns. Nevertheless there is a 

 chitinous termination to this portion in thersites, of very definite 

 form and outline, while in icarus there is merely a chitinous point. 

 This final chitinous armature seems to be of definite peculiar form 

 in each species. A. dainon is the only species examined in which 

 this armature resembles that of A. tJiersites. 



Explanation of Plate LXXXV. 



Agriades escheri. Androconia x 500 and 9 appendages x 25, 

 the latter showing great similarity to those of thersites but markedly 

 larger. The androconia are larger than in either thersites or icarus 

 and have 6 or 7 ribs instead of 4 and 5. 



