CLASSIFICATION OF BUTTERFLIES. 73 



which, if true, might be looked upon as an atavistic relic of its ancestral 

 condition ; but Bar, Burmeister and Miiller say it hangs like other Nym- 

 j)h}ilidac. Moreover, an additional feature appears in the structure of the 

 chrysalis of a large number of the Nymphalidae, whicli would seem to indi- 

 cate that they inherit the mark of the "succinct" condition of their ances- 

 tors, in the straight ventral surface of the entire chrysalis, a feature absolutely 

 without value in its present suspended condition, but full of meanino-, 

 since it is one necessarily common to all tlie close bound members of the 

 higher Succincti, the Lycaenidae. 



The second series wliich one may follow is that which has been seized 

 upon by writers from the earliest times, — the structure of the front legs. 

 In the Hesperidae, the fore legs, like those of the heterocerous families of 

 Le})idoptera, differ in no respect from the others, excepting that the hind 

 tibiae are usually furnished with a pair of spurs at the middle as well as at 

 tlie tip, and the fore tibiae bear a peculiar epiphysis, the use of which is un- 

 known, but which, morphologically, is unquestionably a spur. In the sub- 

 family Papilioninae, the middle pair of spurs of the hind legs is altogether 

 lost, but the fore-tibial epiphyses remain and the fore leg is otherwise 

 entirely similar in character to the other legs. Next, in the closelv allied 

 subfamily, Pierinae, the tibial epiphyses disappear, but the fore leo;s still 

 remain identically like the other pairs. 



As soon, however, as we have reached the Lycaenidae, we notice signs 

 of an approaching abortion of the fore-legs, but only in one sex, the male. 

 In the Lycaeninae, while the fore leg of the female does not differ from the 

 other legs, that of the male begins to lose a part of its armature and to 

 become abbreviated : the tarsal spurs are denuded of scales and both the 

 tibial and tarsal spines are diminished in number ; the paronychia and pads 

 are invariably absent ; and the claws are represented by an apical spine or 

 spines differing from the other spines at most in size. In the Lemoniinae 

 the change has already become much greater ; for, with scarcely an excep- 

 tion, the fore leg of the male has become very much smaller than in the 

 female, and while each part is reduced in size, the tarsus is represented by 

 a diminished number of joints, totally devoid, as is also the tibia, of any 

 armature whatever, but clothed abundantly with long scales and hairs. 

 There is here also sometimes a faint indication of change in the female, 

 the spines of the tarsus being less abundant than on the other legs. 



In the Nymphalidae, the change affects both sexes ; not, liowevcr, in the 

 lowest subfamily, the Libytheinae, which, on this account, many authors 

 who have given special attention to the structure of the legs ha\e classed 

 with the Lemoniinae. But in all other Nymphalidae we have for the first 

 time both sexes represented in the atrophy of the fore legs, and the abor- 

 tion is also carried to a far greater extent. They are also frequently fur- 

 nished, especially in the male sex, with a spreading brush of long hairs. 



