No. 376.] THE WINGS OF INSECTS. 251 
The hind wing of the same nymph (Fig. 22) presents a very 
similar arrangement of trachez, except in a greater reduction 
of the radius. 
Unfortunately, we did not rear any adults from nymphs of this 
species; hence we cannot give a figure of the adult wing of this 
particular insect. But an examination of many Pentatomids 
shows that in the thickened portion of the fore wing the 
trachez follow essentially the same course as in the nymph 
figured here. There are also faint longitudinal veins in the 
membranous terminal portion of the wing which doubtless 
Fic. 22. A Pentatomid, hind wing, nymph. 
correspond with the tips and branches of the principal trachez. 
But at the base of the “membrane,” as this terminal portion 
is designated by writers on the Hemiptera, a hinge line is 
formed, across which it is rarely possible to trace the trachez 
in dried specimens. The veins of the membrane appear to be 
connected by cross-veins parallel with this hinge line and close 
to it, and have but slight connection with the veins of the basal 
part of the wing except near the end of the anal furrow. We 
are not able, therefore, with the material at hand, to work out 
the homologies of the veins of the membrane, and must be 
content with pointing out at this time the more important 
features of the thickened portion of the wing. 
In those Pentatomids in which we have been able to trace 
the courses of the tracheze of the wings, the wing-veins are 
comparatively inconspicuous. We figure on this account one 
