402 SAMUEL H. SCUDDER ON 



to the original specimen, has been sent me by Mr. AV. F. E. Gurley. It is incomplete 

 and the best face is broken into several fragments, but it shows the greater part of the 

 costal margin with the outer tip of the wing. Though the wing tapers apically, this tip 

 is not at all pointed, as was snpposed from the original imperfect specimen, but well 

 rounded, and the costal margin is i)retty ix'gulai-ly and gently ronnded but a little 

 flattened beyond the basal two-fifths of the wing, where there is a slight change in 

 the curve, due to this flattening. As in the oi-iginal, two or three of the mediasti- 

 nal rays are forked near their origin, and the mediastinal area appears to extend a 

 very little further than in the original. AVhat can be seen of the other areas (the 

 scapular vein is nearly complete, but only a little of the others) agrees tolerably well 

 with those of the original specimen, except that the externomedian vein certainly be- 

 gins to fork at an earlier part of its course, namely at about the same point as the scap- 

 ular vein. The wing is preserved a little further toward the base than the original, but 

 only imperfectly, so that little more can be learned from it. None of the anal veins ap- 

 pear. 



Length of fragment, 17 mm. ; probable length of wing, 21 mm. 



The specimen was found at Petty's Ford on the Little Yermilion river, four miles 

 east of Georgetown, Yermilion Co., Illinois, in the same deposits that furnished Prop- 

 teticus infernus Scudd. 



PrOMTLACRIS ("/"^) iiu)My.f)k'^ . 



Prormjlacris Scudd., Proc. Acad. Nat. Sc. Philad., 1885, 34. 



Allied to Paromylaci-is, remarkable like it for its strong convexity, and its stoutness 

 of form, although surpassed by Paromylaeris in both features; the frontal shield is about 

 twice as bi-oad as long, sometimes much less than that, and the wings are considerably 

 less than half as long again as their united breadth. 



The mediastinal vein, though large and abundantly supplied with veins, terminates at 

 about the middle of the wing; most of the branches fork. The scapular and externo- 

 median veins together occupy the greater part of the wing, the latter tei-minating below 

 the tip of the wing, but in the difterent species known they are of varying importance, 

 sometimes the externomedian, at others the scapular, having the predominance; in all, 

 the externomedian branches are long and nearly straight. The internomedian area is 

 narrow, though deep, its veins few and f\\int. The anal furrow which terminates only 

 a little before the middle of the wing is very deeply impressed and the anal area strongly 

 convex and raised, its veins regular, simple or forked, frequent, and strongly curved. 



Indications of legs in one species show that the femora were about as long as half the 

 width ofthetegmina, and about as stout as in the modern species of Periplaneta. 



This genus is closely allied to Paromylaeris, but differs from it strikingly in the much 

 smaller development of the mediastinal area and the course of the scapular vein, which 

 runs through the middle of the wing in Paromylaeris but here considerably above it. 

 The costal margin of tlie wings is much more convex here than in Paromylaeris, the 

 pronotal shield not so broad in proportion to its length, though this is variable, and the 

 whole insect not so stout nor so arched. 



Three species are known which may be separated as follows: 



