222 



THE ENTOMOLOGIST. 



tioned, viz. loss of inner anal nervure, retention of outer anal 

 nervure, with attached rudimentary (VIII), in all groups except 

 Papilionides ; in the latter we have not the rudiment, but an 

 actual nervure = " Grote's vein." It seems to me an indisputable 

 indication that " Grote's vein" is homologous of VIII. 



At first sight it appears remarkable that Papilionids should 

 have retained that nervure, even if homologous of VIII, which 

 has become rudimentary so generally in the Lepidoptera ; but 

 we must regard its persistence in so many groups of the Lepi- 

 doptera, which actually lose one other anal nervure, as evidence 

 that it (VIII) is of actual value as a part of the wing-structure, 

 whether retained as rudimentary or as a "vein" (Grote's), is a 

 matter of degree only ; clearly we have no evidence that VIII 

 and " Grote's vein" are morphologically distinct. 



If we look for evidence of affinity between Papilionides and 

 the other butterflies, we find in generalised Nymphalids (Anosia) 

 a " cubital blotch " on primaries, and a " subcostal-radius con- 

 nection" on secondaries; their identity cannot be doubted, as 

 remnants of the " cubitus-anal connection " of primaries and 

 "humeral cell" of secondaries are retained in Papilionidae. It 

 detracts nothing from their value as indication of affinity when 

 we observe that amongst higher Nymphalids and other groups 

 they are completely lost ; since we find, as Prof. Grote has 

 shown,* that the " cubitus-anal connection " of primaries and 

 the " humeral cell " of secondaries are not present amongst 

 higher Papilionids. 



I can only repeat my original conclusion from a study of the 

 neuration ; f generalised Hesperids, Nymphalid-Pierids, Papi- 

 lionids " represent the 

 surviving links in the 

 continuity of special- 

 ization, a primary 

 modification of neura- 

 tion antecedent to and 

 quite apart from the 

 special modifications 

 peculiar to the several 

 groups-" Thus — 



Neuration of the 

 wings is only one of 

 the many structural 

 characters, imaginal and embryological, which go to establish 

 affinities, any one of which by itself may mislead. May I give an 

 example ? By movement of the fourth radial of primaries, Porina 

 has a different wing-pattern to that of Hepialus ; by neuration, 



- ' Natural Science,' vol. xiv. p. 79, 1899. 

 t Ihid. vol. xiii. p. 395, 1898. 



uA' 2/ rn ph aii fl ,s 

 E jc I s t i n g sp e; cies 



Papilionids 



