S. II. SCUDDER ON PALAEOZOIC COCKROACHES. 49 



wing at the base, and occupies very nearly two-thirds of the costal margin, its limitation 

 next the scapular area being almost straight, a slight sinuosity being scarcely perceptible ; 

 the gently radiating veins of this area are six or seven in number, those next the shoulder 

 simple and distant, the two outer somewhat sinuous, simply or doubly forked and closer. 

 The scapular vein curves gently upward at the base until it has nearly reached the middle 

 of the wing, next passes down the middle or slightly below it, subparallel to the costal 

 margin, and then curves gently upward again, its entire course being very broadly and 

 gently sinuous, terminating at the apex ; it begins to divide at the end of the basal fifth of 

 the wing, almost before it has lost its upward curve, and emits half a dozen oblique 

 branches, the first pair near together, the rest at subequidistant intervals; the second and 

 third are forked near the middle (one of the branches of the former again at the tip), but 

 the others are simple ; they become increasingly longitudinal toward the tip but only to a 

 very slight degree, continuing the decreasing radiation of the mediastinal veins; together 

 these two areas occupy more than half of the wing. The externomedian vein runs in a 

 straight course nearly to the middle of the wing, scarcely turned downward from a longi- 

 tudinal direction ; here it forks, the upper branch again forking near the tip, the lower 

 at less than half way to the border, each of the latter forks again dividing, the upper 

 before, the lower beyond its middle ; all follow a longitudinal direction and occupy upon 

 the margin only the lower half of the narrow apex of the wing. The internomedian 

 vein is remarkably straight throughout and is indeed the only palaeozoic cockroach 

 known in which it is straight; it terminates just before the tip of the wing, commences 

 to divide almost as soon as the scapular vein, and emits, long before the middle of the 

 wing and at regular and short intervals, three straight veins, the first simple, the others 

 forked in the middle, all having a constantly lessening obliquity, so that the outermost 

 fork is parallel to the main vein ; besides these the main vein emits another slight 

 longitudinal branch close to the apex, and the whole area occupies about one-half of the 

 inner border of the wing. The anal furrow is very deeply and sharply impressed and 

 scarcely at all arcuate, running in nearly a straight line to a little before the middle of the 

 wing ; the anal veins, four in number, one of the middle ones forked, are straight, equi- 

 distant and parallel to the furrow. 



The wing is a little above the medium size, 29.5 mm. long, and yet only 9.5 mm. broad, 

 or the breadth to the length as 1 to a little more than 3. It is nearly perfect, being only 

 a little fragmentary about the base and the lower portion of the tip. It is a left wing, of 

 which the under surface is exposed, showing the veins and anal furrow as ridges ; the anal 

 furrow is remarkably prominent, and most of the veins are also very prominent ; this is 

 especially true in the veins of the scapular and externomedian areas ; the internomedian 

 vein itself, as far as its apical fork, is also almost equally prominent, but all its branches are 

 mere lines upon a flat field ; while in the areas covered by the prominent veins the inter- 

 spaces are roundly sulcate, giving additional prominence to the veins ; in the mediastinal 

 area, however, where the veins are somewhat prominent, the interspaces are not sulcate, 

 and the anal area, which must as a whole be broadly vaulted or tumid as seen from the 

 upper surface, partakes of the nature of the internomedian area; the surface itself of the 

 whole wing is smooth, no trace of cross venation being discernible. From its deflection in 

 the reversed specimen, it would seem that the whole costal edge was slightly margined. 



MEMOIRS BOST. SOC. N"AT. HIST. VOL. III. 7 



