8 GROTE — SPECIALIZATIONS OF LEPIDOPTEROUS WING. [Jan. 20, 



forms. It may also be looked upon as a contribution to taxonomy, 

 because the differences noted may find their place in generic de- 

 scriptions and serve to regulate the extension of minor groups of 

 the species. 



I have divided (February, 1897) the Butterflies, or diurnal Lepi- 

 doptera, into two major groups, which may be thus defined : 



Vein ix of fore wing present ; not more than 



one internal vein on hind wing .... Papilionides. 



Vein ix of fore wing absent ; at least two in- 

 ternal veins on hind wing Hesperiades. 



The characters given above to the Papilionides seem, at least in 

 combination, exclusive of all other hitherto discovered Lepidop- 

 tera. The opposed characters will not exclude larger groups of 

 the Moths from the Hesperiades. With the latter the present 

 study is only incidentally concerned. Following modern classifi- 

 catory notions, I have given to the names of these two major 

 groups of the Butterflies an accepted termination {ides), and I 

 would attach to each the taxonomical value of a superfamily. This 

 course seems to be additionally warranted if we accept my assump- 

 tion that the two groups are not immediately connected, their 

 phylogeny distinct and that no nearer blood-relationship exists 

 between them. These two major groups of the Butterflies have, 

 I am led to believe, developed themselves independently, so that 

 the obvious characters which would unite them have been secon- 

 darily acquired, and constitute a parallelism in development. The 

 absolute character of a primary nature which separates the Papili- 

 onides from the rest of the diurnals is the presence of vein ix on 

 primaries. The neurational characters, used here to divide the 

 Papilionides into family and subfamily groups, are in their nature 

 secondary, gradational and recurrent; in other words, characters 

 of specialization only. 



Characters of Specialization. 



The first direction in which specialization shows itself lies in the 

 suppression of the media on both wings. In this generally ex- 

 pressed direction the Papilionides show a course parallel with that 

 undertaken by the Pieridae, with the difference that the middle 



