1912] Pupal Wings of Hepialus Thule 245 
case, in the second case it is all median or anterior arculus. A 
similar atrophy of the anterior arculus may take place and a 
condition like that found in the wings of the muscids 
exist, where media appears to arise from cubitus.. This shows 
how even in the two wings of the same species, as certain Jugate, 
the media may appear to arise from the radius in the front wings 
and from the cubitus in the hind wings. 
Anal Veins.—The front wings of Hepialus thule has two 
anal veins, each represented by a trachea. The first anal vein 
is coalesced for a part of its course with the stem of cubitus. 
many figures of wings of Hepialus show a cross-vein between 
cubitus and the first anal vein, the cross-vein is the true course 
of cubitus. The apparent continuation of cubitus proximad of 
this cross-vein is the posterior arculus. The second anal vein 
lies close to the wing margin and the vein cavity is not well 
developed. The hind wing has three well developed anal 
trachez in three equidistant vein cavities. The vein cavity of 
the first anal vein is not so distinct as the others. 
