CAEBONIFEROUS COCKROACHES. 405 



Tlie fore wings have a well developed angulate humeral lobe, so that the curve of the 

 prothorax is hardly interrupted in passing to the wing; the costal margin is regularly but 

 not strongly convex, much less convex than in either of the other species, so far as it can 

 be traced. The mediastinal area is triangulai-, broad at base and rapidly narrowing, ter- 

 minating at the middle of the wing and slightly beyond the anal furrow; the radiating 

 veins are almost perfectly straight and only the outer ones fork and then but singly and 

 deeply. The scapular vein is almost rigidly straight, stiffly forking beyond its basal 

 fourth, the upper branch again dividing in a similar way near its base, and altogether 

 much resembling a continuation of the mediastinal vein, and covering on the margin 

 only the proximal half of the outer half of the wing. The externomedian vein is simi- 

 larly rigid in its ujjper half, but in its lower shows the proximity of the more arcuate 

 internomedian; it divides close to the base into two branches, the upper of which mimics 

 the scapular, forks once before the middle of the v/ing and probably again beyond, while 

 the lower with a downward curve, scarcely perceptible in the part preserved but no 

 doubt more pronounced beyond, forks a little earlier than the upper branch, each fork 

 again dividing at about the middle of the wing; this vein evidently holds the tip of the 

 wing in its grasp. The internomedian vein, feeble in strncturc, is gracefully arcuate, 

 but otherwise closely resembles the preceding; for it divides in two branches close to the 

 base, the upper forking just before the middle, the lower sending out two or three arcu- 

 ate simple or forked veins to the inner margin. The anal furrow is sharp and deep, 

 considerably curved, terminates considerably before the middle of the wing, the anal area 

 well domed, with numerous, ])arallel, mostly simple and deeply forked veins, the outer 

 ones more arcuate than the others and simple. 



The hiiul wings are exposed apically but not enough to show much of the structure 

 of the wing for want of the vein-attachments. It would appear, however, as if the scapu- 

 lar area were very broad and nearly uniform in the distal half of the wing with relatively 

 few, oblique, moderately distant, straight branches; that the externomedian was not 

 greatly difl'erent from what appears on the fore wing; and that the rounded apex was 

 somewhat pointed. • 



Length of entire fi-agmentas misplaced, 43 mm. ; probable length of creature, 37 mm. ; 

 length of prothorax, 12.5 mm.; breadth of same, 16.5 mm.; probable length of fore wing, 

 28 mm.; apparent breadth of same, 1G.5 mm. 



One specimen from Mazon Creek, received from Mr. R. D. Lacoe under the number 

 208Gab. 



PaROMYLACRIS (^«>"?'i MoXay.pk) 



Paromylacris Scudd., Pi'oc. Acad. Nat. Se. Philad., .1885, 35. 



An exceedingly broad, rounded, and well arched cockroach, in which the pronotal 

 shield is broadly rounded in front and slightly convex behind, broad in proportion to its 

 length, and the wings not half so long again as their united breadth. 



The wings in the only specimens known are imperfectly preserved, but sufficiently to 

 show that the species cannot fall into any described genus of Mylacridae. The medias- 

 tinal vein of the upper wing consists of at least seven or eight principal branches origi- 

 nating near the middle of the base of the wing, several of them forking close to the base 



