1899.] GROTE — SPECIALIZATIONS OF LEPIDOPTEROUS WING. 31 



veins, and in the striped character of the ornamentation. It prob- 

 ably occupies an independent intermediate position. The colors 

 in this group, brown and greenish yellow, are peculiar, and, in 

 preparing the wings in the usual manner, they are persistent. 

 Pathysa has striped wings. In Arisbe the bands are indicated by 

 scattered blotches. These latter are gathered into a single series of 

 interspaceal spots in Idaides, on the primaries. These spots 

 coalesce and broaden into a band, which also obtains over the hind 

 wings, in Ze tides. 



The coincident characters of Pathysa and Iphiclides allow of no 

 other conclusion than that the two are somewhat nearly phyloge- 

 netically connected, notwithstanding the fact that in Pathysa the 

 first branch of radius joins subcosta, while in Iphiclides it is free. 

 Assuming that the Second Group contains younger forms, we might 

 have in Iphiclides a type representing a stage through which Pathysa 

 has already passed. But Iphiclides and the members of the Second 

 Group are in one character more generalized than Papilio and its 

 immediate allies, i.e., the straight internal vein of hind wings. We 

 have probably to do with divergencies from a common stock in 

 different directions, in part retaining characters of generalization. 

 It is sufficient here that we show that Iphiclides and Papilio 

 constitute totally distinct genera, having probably a different 

 immediate ancestry. And it remains a possibility that the 

 fusion of the first radial branch with subcosta is a more recent 

 feature, here engrafted upon a wing in other characters representing 

 an older type than Papilio. Thus the Idaides group may be a 

 lateral branch, thrown off before the tendency of the internal vein 

 to curve and shorten on hind wings was developed. And to this 

 branch, as represented by Pathysa, Iphiclides podalirius and allies 

 may be related. In respect of the curved inner margin of the hind 

 wings, Papilio machaon and allies are more specialized than 

 Iphiclides. 



• (3d Group.) 

 Pachlioptera aristolochicB. 



The shape and neuration of primaries agree exactly with Eurycus, 

 except that the cubital cross-vein, while narrowing inferiorly, ap- 

 pears to reach vein vii, forcing the submedian fold down to the 

 vein. On secondaries the humeral cell is smaller and vein iv, ter- 

 minates in a spatulate tail. Veins ivj and iv, are not so near at 



