742 PROCEEDINGS OF THE NATIONAL MUSEUM. voi,. xxix. 



EXOCHOBLATTA HASTATA (Scudder). 



retrablallina hadata Sci'ddku, Bull. I'. S. ( ieol. Surv., No. lL'4, 1895, p. 141, pi. 

 XI, %. 10. 



Lond'dij. — Cassvill(\ ^^^'st Viriiiiiia. Duiikiird foi'inutioii; Lower 

 Permian. 



IIolott/pe.—OAt. No. 38205, U.S.N.M.* 



ACOSMOBLATTA, new genus. 



This ^-emis is likewise derived from the Phylohlatta type, from 

 which it is distinguished by a strono- reduction of the radius with a 

 correspondino- enlargement of the media. The form of the wing is like 

 that in J*}iy/()hl((tt<(, about 2^ times as long as broad. The liand-shaped 

 costal area takes up at least two-thirds the length of the wing. The 

 radius does not extend quite to the tip of the wing and gives off 

 anteriorly but 2 simple branches; instead, however, the first branch 

 of the media separates in 4 to 5 twigs. The 3 following branches of 

 the media are normally directed toward the apical margin. The cubi- 

 tus, as well as the anal area, are similar to those in Phylohlattd. Cross 

 veins very delicate. 



Type of genus, Acoxmohhiftn permdcra (Scuddei-). 



ACOSMOBLATTA PERMACRA (Scudder). 



Gt'r(tl>l(itliiia perinacra Scudper, Bull. U. S. Geul. >Surv., Nu. 124, 1895, p. 121, pi. 

 X, fig. 13. 



Locality.— CussvWle, West Virginia. Dunkard formation; Lower 

 Permian. 



ACOSMOBLATTA EAKINIANA (Scudder). 



Etohlatt'ma mkmiaud Scudder, Bull. IT. S. Geol. Surv., No. 124, 1895, p. 88, ]il. 

 VII, fig. 1. 



Zr>c'«//^//. — Cassville, West Virginia. Dunkard formation; Lower 

 Permian. 



JI<>Iotyj>e.—Ci\t. No. 38169, U.S.N.M. 



AMBLYBLATTA, ne\^ genus. 



Front wing broad, truncate, with somewhat diminished base, twice 

 as long as wide. Costal area band-shaped, occupying nearly the entire 

 anterior margin. Radius vaulted and ending nearly in the center of 

 the apical border, with 2 furcate and 2 simple branches. Media 

 strongly arcuate, with 2 dichotomous and 1 simple offshoots, which 

 are directed forward toward the apical margin. The arcuation of the 

 cubitus is S-shaped, and the vein fuses in the apical margin, with T 

 mainly simple l)ranches directed backward. Anal area short, defined 

 t)y a very strongly curved fold, with 5 veins. Distinct tremulous 

 cross lines. 



