94 FOSSIL BUTTERFLIES. 



In his description of the insect Mr. Butler compares the neuration to that of 

 Caligo, and says its nearest allies are Caligo, Dasyophthalma and Brassolis. In 

 his latter paper he figures the wing of a Dasyophthalma by way of comparison. 

 In the genera named all the branches of the subcostal nervure are simple, and are 

 thrown off from the superior surface, excepting the single set which is emitted from 

 beneath, and which marks (as in all butterflies) the limit of the discoidal cell ; this 

 corresponds fairly with the first set of inferior veins emitted by the subcostal vein 

 in the fossil; for the other sets, however, no counterpart will be found in the living 

 types. 



It was probably Mr. Butler's want of familiarity with fossils that led him to 

 overlook several features which can be seen in these originals. Having first traced 

 the outline of the wing and the general course of the veins directly from the 

 specimens, I subsequently filled in by measurement all the other parts which I 



could follow, studying each vein, or supposed 

 vein, with the utmost care, from one end to 

 the other of its course. The result of that 

 study is presented in fig. 8, which differs es- 

 sentially in its details from the illustrations 



Fig. 8. 



? Butlel> ' alld 1O kS ' &S he himself 



P^ontina oolitica Butt. 



corrected sketch of the ..euration. confesses, "exceedingly anti-lepidopterous." 



In the first place, the wing is much narrower than depicted by him; and at the 

 extremity of a vein (the submedian vein of Butler's sketch) there is a slight but 

 decided bending inward of the membrane, as very frequently occurs at the line 

 of demarcation between the middle and inner area of the wing in all or nearly 

 all the lower suborders of insects, but never, so far as I am aware, in Lepi- 

 doptera. What he has given as a simple costal vein is neither swollen at the 

 base nor simple, but has two inferior branches near the middle of the wing, 

 united near their origin by an oblique cross vein. Branching of the costal vein 

 is unknown in Lepidoptera; but if it should be claimed that this might be the 

 subcostal, just as much difficulty will be encountered with the structure and re- 

 lationship of the veinlets below, which must then be considered as belonging 



