Mr. Edward Doubleday's Remarks on the Gtnw Argvnnis. \s\ 



merely a faint line extending from the disco-cellular to the base, evidently nol 



tubular. 



Thus in Castnia, where it branches about the middle of the discoidal cell, the 

 upper branch is often almost atrophied; in Heleona militaru it is in 1 1 » i - Btate 

 throughout its whole course; in Urania and Leiocamp'a its course is indii 

 by a line, which shows no symptoms of being tubular, and which in the latter 

 genus does not reach the base. One step more and it has vanished from the 

 wing, though sometimes in certain lights a faint trace of it may with difficulty 

 be detected. A close examination of the wing will always show a partially atro- 

 phied disco-cellular, connecting these nervules of the discoidal with cither the 

 subcostal or the median nervures, even where one of them lias been described 

 as quite free. 



We thus see the discoidal nervure becoming gradually atrophied until only 

 its nervules remain ; and as air must in some way penetrate into them, they 

 are, when the parent trunk has vanished, attached to the nervure immediately 

 above or below them, or to both. 



Admitting the correctness of the above views, we have in the Rhopalocera a 

 median nervure with constantly three nervules, above which are the two di>- 

 coidal nervules, then the subcostal nervure generally offering five nerval.-. 

 but sometimes only three. In the Suspend the number of these nervules is 

 almost invariablv five, but in the Succincti it is more variable, especially in 

 the Enjchidce. Not unfrequently these nervules anastomose with the costal, 

 as in some species of Papilla and Damns and in Hecalene Ckftemnvtr*, &c. 

 Leptocercus presents an almost solitary instance of a bifurcation of one of tl« 

 nervules ; but perhaps the more correct view of this would be to consider that 

 two nervules coalesce at their base in a manner analogous to the union of the 

 costal nervure with the first subcostal nervule in some Species of Dtmaus. 



The genus Argynnis of Godart always oners five subcostal nervules, neve, 

 I believe, anastomosing with the costal nervure. 



If we remove from it three species, Ar g . Alcanira, Aceste and L^ and 

 add to it some of the CethosUe, it is, as I have already said, a ,„«. < 

 group. Perhaps a fourth species, Arg. Metea **J^££ 

 I only know it from Stoll's figure, winch leads me to believe 



dema. 



3 r2 



