Taxonomic value of Genital Armature in Lejndoptera. 315 



classificatory purposes, so it is with the sexual armature of 

 Lepidoptera, and my desire is, in this paper, to lay before 

 ' my fellow systematists, at least those of them who are 

 sceptics on this point, some facts illustrated by figures to 

 enable them to see that there is very much more value to 

 be found in these organs than they have hitherto been 

 wilhng to admit. 



I will begin my evidence with that group of the Rhopa- 

 locera that I have made my special study — the Ruralidae, 

 i. e. the Lycaenidae, Auct., but it will of course be necessary 

 to consider other famihes as well. I will first compare 

 Plebeius argus, L., and Polyormnatus icarus, Roth. ; if the 

 figures are compared it will be seen that the clasps, PI. LV, 

 fig. 1. of argus are much broader than those of icarus, 

 PI. LV, fig. 2 ; that the aedoeagus, PI. LV, fig. 1, of 

 argus is much larger (especially longer) than that of icarus 

 and is quite a different shape, and that the laterals of the 

 tegumen in argus, PI. LV, fig. 1, are decidedly slighter than 

 those of icarus, PL LV, fig. 2. Now these are not specific 

 variations ; there is a considerable section of Staudinger's 

 " omnibus genus " Lycaena that follows the general " build " 

 or form of the armature of argus, and there is another 

 considerable section that follows the general build of icarus. 

 The question then arose, Is there any other character 

 confirming their separation, inasmuch as the neuration is 

 practically the same ? This character is forthcoming, the 

 eyes of the argus group, i.e. the genus Plebeius, are glabrous, 

 whilst the eyes of the icarus group, i. e. the genus Polyom- 

 matus, are hairy. I am aware that certain workers, even 

 of my personal friends, would disregard this character, but 

 I cannot follow them ; the character persists in each genus 

 and it does not seem to me to be reasonable to ignore it, 

 especially when it is a confirming point. Over twenty 

 years ago in these Transactions (1892, p. 27) I was induced 

 by these characters to remove tengstroemi and its allies from 

 that same " omnibus genus " Lycaena to another almost 

 equally " omnibus " genus Thecla, since when de Niceville 

 has created another genus for that httle group, viz. Neoly- 

 caena, naming for its type sinenis, Alph. Staudinger and 

 I think nearly all others have accepted the transference 

 without a question. 



The genus Habrodias was created by Scudder in 1876 

 (Bull.- Buff. Soc, iii, p. 136) for grunus. The male 

 armature was not taken into considerat on. the neu^ 



