S. H. SCUDDER ON PALAEOZOIC COCKROACHES. HI 



terminates near the end of the middle third of the wing ; in the fragment, which represents 

 all but the basal fourth, there are about eight feeble, simple, gently arcuate, rather distinct, 

 longitudinally oblique branches, and the middle breadth of the area is scarcely less than 

 one-fourth the width of the wing. The scapular vein, in the basal third or fourth of the 

 wing, runs in very close proximity to the mediastinal vein, then diverges from it, being 

 directed toward the apex of the wing ; but a little past the middle it returns by a broad 

 curve to its former trend, and terminates probably just before the extreme tip of the wing ; 

 in the fragment it emits four branches, and in the apex, which is destroyed, it probably had 

 one or two more ; the first of these four is thrown off where the vein diverges from the 

 mediastinal, viz., a little beyond the basal third of the wing; and this branch continues 

 subparallel to the mediastinal vein, but is compound, forking once next the second forking 

 of the scapular vein, each fork again dividing at unequal distances before reaching the 

 border ; the other branches are simple, and originate at unequal distances apart, the second 

 in the middle of the wing. The externomedian vein follows very nearly the same sinuous 

 course as the scapular, but constantly a little divergent from it, and widely distant from 

 both it and the internomedian vein ; it emits its first branch midway between the first 

 two branches of the scapular vein ; this forks at least once, but probably only once, at less 

 than half way to the apex ; a second branch, not shown on the plate, and obscure' upon 

 the fossil, arises opposite the fifth internomedian branch, but only its base is preserved. 

 The internomedian vein, so far as it is clearly preserved, is straight, and considerably 

 oblique, being parallel to the general trend of the middle portion of the externomedian 

 vein, and, in this portion of its course, it emits five equally and widely distant, generally 

 forked branches, which are oblique at origin, and excepting the first, very strongly arcuate 

 beyond, becoming nearly longitudinal ; directly beyond the origin of the fifth branch, or 

 just at the end of the middle third of the wing, the vein itself becomes longitudinal, and 

 runs scarcely convergent with the margin, probably ending in the middle of the apical 

 third of the wing, 1 and thereafter emits one or two more simple branches. 



The wing is of medium size, the fragment measuring 19 mm. in length and 10 mm. in 

 breadth; probably the entire length of the wing was 25 mm., making the breadth to the 

 length as 1 : 2.5. The upper surface of a left wing is exposed, and the more essential parts 

 of the neuration are present, although the entire anal area, with the corresponding upper 

 portion of the base, is gone, together with a large fragment from the apex of the wing. 

 The most characteristic feature in the wing, one found apparently in no other palaeozoic 

 cockroach, is the peculiar limitation of the cross neuration to broad, piceous belts, which 

 follow the veins and their branches throughout all parts of the wing sufficiently preserved 

 to see it, excepting the branches of the mediastinal vein ; they are apparently worn from all 

 but the basal portion of the scapular and externomedian veins, to the extent represented in 

 the plate ; but, wherever they can be seen, follow each of the veins and their branches 

 with extreme regularity and nearly equal width, so as to cross the interspaces where these 

 are narrow ; the cross veins in these belts are very delicate, crowded, elevated, a little 

 irregular, but usually transverse to the interspaces, and only to be seen by the aid of a 

 magnifier ; between the bands, which are about 0.75 mm. in breadth at the widest, no 



1 The outside mark on the plate (fig. 9), representing be removed considerably further toward the tip of the wing. 

 the termination of the internomedian area, should therefore 



