100 S. H. SCUDDER ON PALAEOZOIC COCKROACHES. 



G-erablattina clathrata. PL 3, fig. 4. 



Blattinn clathrata Heer, Viertelj. naturf. Gesellsch. Zurich, is, 288, 294-96, pi., figs. 3, 3 a 



3 b ; — Gold., Faun, saraep. foss., ii, 19. 



Fore wing. The extreme tip and most of the anal area are wanting, and the inner mar- 

 gin is also broken, so that the precise form is uncertain; it is, however, tolerably broad, 

 and the costal border rather strongly and regularly arcuate, much as in the preceding 

 species, but with a very slight humeral lobe; the principal veins are all almost similarly 

 arcuate, originating near the middle line of the wing, and running subparallel to the costal 

 margin ; the branches on either side being very frequent, long, and straight, and. parting 

 from their stems at an equal angle, give the wing a peculiarly simple appearance. The 

 mediastinal vein runs nearly parallel to the costal margin, but is more distant from it in the 

 middle than at the base of the wing, is bent at the origin of its first branch, the humeral 

 lobe being devoid of branches, begins to approach the margin a little beyond the middle of 

 the wing and terminates at the very end of the fragment, or probably about midway be- 

 tween the middle of the costal border and the extreme tip of the wing ; it emits about a 

 dozen closely-crowded, straight or nearly straight, simple or occasionally apically-forked, 

 oblique and nearly parallel branches, the direction of the apical not diverging greatly from 

 that of the basal branch ; the area is very broad, occupying nearly one-third the breadth of 

 the wing. Tbe scapular vein, appearing to originate from the same stem as the externo- 

 median and to separate from it in the middle of the basal half of the wing, runs close and 

 parallel to the mediastinal, until that vein turns toward the costal margin ; it retains there- 

 after its former direction for some distance, and then turns very slightly and gradually up- 

 ward, and terminates just before the tip ; in this apical portion it emits three closely 

 approximated branches, the first next the last branch of the mediastinal vein, and basally 

 forked, the others simple and soon parallel to the main stem. The externomedian vein 

 does not fork until past the middle of the wing, and, just this portion being destroyed, it 

 is impossible to give a precise statement, but in any case the distribution of the veins is 

 peculiar, for the three or four straight and simple branches, which occupy the tip of the 

 wing and run subparallel to the scapular branches, spring, in the apical fourth of the wing, 

 from a vein which runs almost exactly parallel with the costal border, and in continuation 

 of the main externomedian vein ; while the other three or four branches, which strike the 

 apical part of the inner margin, run parallel to the internomedian branches, and are much 

 longer than the other externomedian branches, running parallel to each other in a straight 

 and simple course, and originating, in some indeterminable manner, scarcely beyond the 

 middle of the wing. Tbe internomedian vein is rather strongly and very regularly 

 arcuate, terminates a little nearer the apex than the mediastinal area, and emits about ten 

 nearly straight, very long, parallel, oblique veins, the first doubly forked, the others simple; 

 the area at its broadest occupies considerably more than half the breadth of the wing. The 

 anal furrow is well impressed, strongly arcuate, apically nearly straight, terminating not 

 much beyond the basal third of the wing ; one or two fragments of anal veins next to the 

 furrow are preserved, running parallel to the same. 



The wing is of rather large size, one of the largest of the genus, the fragment measuring 

 32 mm. in length, and 13.5 mm. in breadth; the whole wing is probably 35 mm. long, 

 according to Heer, the breadth being to the length as 1 : 2.6. By some accident it has 



