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 (Aiiosia) 

 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. 



yrti pha I i cl s 

 Existing sp ecies 



Papilionids 



