86 S. H. SCUDDER ON PALAEOZOIC COCKROACHES. 



strong basal curve, is straight, subparallel to, but a little divergent from, the costal margin, 

 and terminates beyond the apex of the wing ; it commences to divide a little beyond the 

 basal quarter of the wing, and emits about seven longitudinal branches at subequidistant 

 intervals; the first is compound, beginning to branch next the apical curve of the medias- 

 tinal vein ; the others are simple or forked, or rarely doubly forked, and fill the apex and 

 apical third of the costal margin witli straight, crowded veins. The externoinedian vein, 

 beyond its basal curve, runs parallel to the preceding throughout, but before it forks, in the 

 centre of the wing, is rather distant from both the scapular and internomedian veins ; it 

 emits three inferior branches, distant at their bases, the first two doubly forked, the last 

 simple, the branches all closely crowded, as in the preceding area, and occupying rather 

 less than the apical fifth of the inner margin. The internomedian vein, beyond its basal 

 curve, is straight, only curving downward a little at the extremity, which reaches the bor- 

 der only just before the apical sixth of the wing ; it commences to branch before the end 

 of the basal fourth, and emits about seven branches, simple or forked, the basal ones trans- 

 verse, oblique, and sinuous, the apical longitudinal, oblique, and nearly straight. The anal 

 furrow is very deeply impressed and strongly arcuate, terminating before the basal third 

 of the wing ; the first of the anal veins is nearly as arcuate as the furrow, moi - e distant 

 from it basally than apically, and has a couple of branches; the others are generally simple, 

 oblique, nearly straight, and crowded. 



The insect is of medium size, the wing measuring, as preserved, 23 mm. in length, and 

 9.5 mm. in breadth ; the entire length was probably 26 mm., and the breadth to the length 

 as 1 : 2.74 ; only the tip of the wing is wanting, with the apical third of the costal margin. 

 It is the upper surface of a right wing. The anal area, especially next to the furrow, is 

 rather tumid, rendering the depth of the furrow much more apparent ; on the contrary, 

 there is a depression in the central parts of the humeral lobe ; excepting the anal furrow, 

 the mediastinal vein is more distinctly impressed than any ; the branches of this vein, and 

 those of the two following veins, as well as the veins themselves, are rather obscurely 

 impressed, while the veins and branches of the internomedian and anal areas are delicately 

 raised like tracery; the surface is very flat, and the whole is covered with an obscure net- 

 work of polygonal cells of raised lines, which become more distinct in the anal and medi- 

 astinal areas, where they are mostly changed to transverse lines, frequently forking in pass- 

 ing from one vein to another, or uniting with the neighboring cross vein. 



Hind wing. A fracture of the front wing, beyond the middle of the costal margin, with 

 the removal of the parts beyond it, leaves exposed a "fragment of the corresponding portion 

 of the underlying right hind wing. Indeed, as I have proved by experiment, the upper 

 wing may be peeled off from the lower ; the piece broken off, carbonaceous in appearance 

 throughout, represents not only the upper wing, but the film of detritus which lay between 

 the two wings after deposition ; for it shows upon the one side (the under) sharply raised. 

 delicate lines, corresponding exactly in reverse to the sharply impressed veins of the under 

 wing ; while upon the upper surface are faintly impressed lines which are not opposite those 

 on the other surface of the lamina, but represent the veins of the upper wing. The frag- 

 ment of the hind wing thus exposed is very small, and covers the outer half or third of 

 the costal border. The veins have the closest resemblance to those of the front wing, 

 beyond which they lie, and almost appear as their continuation ; the veins represented on 

 Plate 6, fig. 6, above the mark separating, for the front wing, the mediastinal and scapular 



