106 



THE PALEONTOLOGICAL DATA 



A somewhat more specialized species is Eurythmopteryx antiqua (Fig. 

 io8). Here too are found definite cross- veins and the accessory veins 

 appear to have a definite arrangement. The most stril<:ing feature of the 



Sc 



Fig. 107. — Stygne Roemeri (After Handlirsch). 



cubitus in this wing is the fact that vein Cui is simple while vein Cu2 bears 

 two, forked accessory veins; a curious result of this is that the three 

 branched veins in this wing, the radius, the media, and the cubitus resemble 

 each other to a remarkable degree; in fact each is of what I have termed the 

 isolated front branch type in my discussion of the media. In many of the 

 Palseodictyoptera the cubitus is of this type But in many others vein Cui 

 bears as many or even more accessory veins than does vein Cu2. This is 

 the case in the two older insects, Paolia vetusta and Stygne Roemeri, described 

 above. 



The fourth wing from the Lower Upper Carboniferous in which cubitus 

 is preserved is Pseudofotiquea camhrensis (Fig. 103). If the figure correctly 

 represents this vein it is of so unique a type that it must be regarded as a 

 sidewise development, resembling nothing of which we know that either 

 preceded or followed it; and consequently it throws no light on the ques- 

 tion regarding the primitive form of the cubitus. 



^^* /^l 



Cm I 



Fig. 108. — Eurythmopteryx antiqua (After Handlirseh). 



In marked contrast to the isolated front branch type of cubitus is a 

 type in which vein Cu2 is simple and vein Cui bears accessory veins, which 

 might be designated as the isolated hind branch type of cubitus. An illus- 



