186 THE CANADIAN ENTOMOLOGIST. 



given in the second part of the Syst. Lep. Hild., published April 19, 

 1900. It is probable that but for these publications the new Catalogue 

 would have begun with the Nymphalidne. 



A discussion of the homology of the second radial branch in the 

 Pierids with reduced radius follows the author's expressed preference for 

 the amended Redtenbacher-Comstock system of notation for the veins. 

 According to Spuler, the second radial branch in Pieris should be 

 notated 2 + 3, but a fusion of these branches is not demonstrated in the 

 pupal wing. Grote's theory of the movement of the radial branches is, 

 that they pass off by the tip of the wing. This is true especially for 2 to 

 5. Now, in Pieris the second radial remains in its original generalized 

 position, near Ri, above the cell. It does not seem probable that R3 

 could ever move backwards to fuse with R2. The reduced radius of 

 Pieris receives compensatory mechananical support through the advance 

 here of the first median branch from below. In the Nymphalids, where 

 the radius is never reduced and remains in a generalized five-branched 

 condition, the upward movement of the median branches is stayed. 



The paper closes with a brief summary of the fossil remains of 

 Lepidoptera published. These remains, though too few to be decisive, 

 favour the author's view, as to the butterflies, that the Nymphalids and 

 Hesperians represent older groups of the line to which they belong. 

 The nearer relation between the two has been made evident by the 

 author's discovery of the " long fork ' : in Charaxes (c. f. Proc. Am. Phil. 

 Soc, 1898, 39), which indicates the way in which a wing of the Hesperid 

 type may have passed into one of the type of wing shown by the brush- 

 footed butterflies. A resemblance is shown also in the generalized radius 

 and the consequent unwillingness of the median branches to leave the 

 cross-vein. All these observations tend to support a mechanical source for 

 the changes in the neuration. 



The author considers the Lepidoptera to be a relatively younger 

 branch of the insects. The possible conclusion to be drawn from their 

 fossil remains is, that from Tineid-like forms existing in the middle period 

 of the earth's history there was a rapid development in the Tertiaries, 

 where we meet with butterflies already quite like the Nymphalids and 

 Skippers of the present day. The meagreness of the material precludes 

 the formation of any final opinion. — Communicated. 



Mailed July 2nd, 1902. 



