326 SAMUEL II. SCUDDER ON TIIK 



leasl as Long as broad. Front wings obovate, the costal margin slightly less arcuate in the 

 middle than at either extremity, the mediastinal vein subparallel to the costa and termina- 

 ting near the apical third of the wing, with rather distant simple branches ; scapular 

 vein terminating near the tip, with longer and usually forked but otherwise similar branches. 

 Externomedian vein very important with numerous, very long, generally forked, curving 

 branches, subparallel to the outer half of the costal border. 



G-erapompus blattinoides s|>. nov. PI. 29. fig. 1. 



The general aspect of the closed wings is that of a cockroach. The prothorax is sub- 

 cordiform, not unlike that of some Carabidae, with a blunt subcentral boss; the parts in 

 front are obscure. The hind leg is rather long, the femur much stouter than the shorter 

 tibia, the tarsi obscure but nearly as long as the tibia. Wings slightly produced at the apex, 

 but well rounded, less than three times as long as broad. Scapular vein first forking some 

 way beyond the middle of the wing, at or beyond the last fork of the mediastinal vein, and 

 then at once curving downward to approach the margin less rapidly. Length of prothorax 

 3.5 mm., hind tibia 4 mm., breadth of hind femur 1.5 mm., length of front wing 20 mm., 

 breadth of same 7.5 mm. 



The carboniferous beds of Mazon Creek ; discovered by Mr. F. T. Bliss. 



G-ei apompus extensus sp. nov. PI. 29, figs. 5, 8. 



The prothorax is quadrate, the mesothorax of the same width in front as the prothorax, 

 but widening posteriorly; the head apparently a little smaller than the prothorax. Fore 

 wings tapering apically but rounded at the tip, less than three times the length of their 

 median width, the costal margin less arcuate than in the preceding species. Scapular vein 

 nearly straight, first branched near the middle of the wing, some distance before the 

 final forking of the mediastinal vein, and unaccompanied by any change in the direction of 

 the stem. Hind wings, very similar to the front wings in size and shape but with the brandies 

 of the externomedian vein much more transversely oblique and curving in the opposite 

 sense, their open side being toward the tip of the wing. Length of prothorax 3 mm., 

 breadth of same 3 mm., length of front wings 30 mm., median width of same 11 mm. 



Mazon Creek, Mr. R. D. Lacoe, No. 2019. 



Anthracothremma (a v 9 P o|. Bp^a) gen. nov. 



Body stout, apparently depressed, the thoracic segments several times broader than long, 

 tapering anteriorly to a subtriangular head and more gradually behind along the almost 

 parallel-sided abdomen, broader at tip than the head. Wings elongated, with nearly 

 straight costal margin, extending far beyond the abdomen ; the mediastinal vein extends 

 over about two-thirds of the wing ; the scapular vein rather strongly arcuate, and reaching 

 very near to the tip ; the externomedian vein closely parallel to the latter, commencing to 

 branch before the middle of the wing and emitting many long, parallel, simple or simply 

 forked, straight or gently curving, longitudinally oblique branches ; internomedian branches 

 similar. 



