1809.] GROTE — SPECIALIZATIONS OF LEPIDOPTEROUS WING. 41 



is the simplest existent form with the veins all separate. A move- 

 ment in specialization of the radial branches, normal with the lepi- 

 doptera, changes this wing into that of die lyCcX-nids. Both are 

 now specialized and hardened types, and the position of the median 

 branches has become so fixed that, in their specialization, the middle 

 branch will not yield and submits to extirpation in situ. The condi- 

 tion of the hesperid wing is nearly reproduced in Charaxes, and 

 proves that this was the original condition also of the Pieri-Nymphalid 

 branch. It has been abandoned in specialization through the pro- 

 cess of absorption and furcation of the veins ; thus the hesperid 

 type of wing becomes the unit underlying all the wing types of the 

 Hesperiades. Into this group, so closed, and having the internal 

 vein (vii) forked at base (viii), we can nowhere properly inter- 

 polate a group possessing an additional vein (''ix") and having 

 no fork (viii) to the internal vein (vii), although, as a matter of 

 theory, we may contend that the papilionid wing had also primarily 

 separated veins. 



I conceive, then, the Hesperiades to be monophyletic, a develop- 

 ment of a single branch or stem of the lepidopterous tree, and as 

 being independent of the Papilionides and their ancestry. As 

 compared to the Papilionides, the rest of the butterflies are in the 

 position of the Noctuid branch when compared with the Saturn- 

 iades. This parallel is not a little exact. The development in 

 evolutionary changes of the Papilionid wing is closely copied by 

 the Saturniadae, which have but one anal vein on hind wings. 

 We have the same hollowing out of the inner margin in both groups 

 among specialized forms. The Hesperiades resemble generalized 

 moths in having two or more internal veins, and although these are 

 convergent characters, not of phyletic value, they sustain the 

 parallel. The exclusiveness of the Papilionides is supported by 

 vein ''ix " of primaries. Wiien we take into account their total 

 wing-structure, the idea that we have to do with a radically 

 different development of the lepidopterous type becomes more and 

 more reasonable. I separate, therefore, riot the Hesperiadce, but 

 the Papilionides from the rest of the butterflies, and herein I differ 

 from other authors, no less than from Comstock. 



The general inequalities of all the specializations preclude, to a 

 great extent, the question of rank, which practically becomes a 

 matter of more limited importance within the confines of a single 

 group. And I may repeat here, that the specializations of the 



