KO. 2337. NEW AMERICAN FOSSIL INSECTS— COCKERELL. 303 



of which forks near margin ; lower branch of radius forking a little 

 before level of fork of upper, both divisions again forking, the upper 

 by its branching enclosing six cells on margin, the lower with each 

 division at least once forked, the inferior much sooner than the su- 

 perior; media very straight, forked a little beyond origin of third 

 branch of cubitus, the lower division soon forking again, the two 

 together by their branching enclosing at least seven cells on margin ; 

 primary branches of media four, all except the first distinctly above ; 

 cubitus long, not rapidly descending, ending far beyond middle of 

 wing, with no distinct superior appendage, but the last three forks 

 are symmetrical, the branches are six, very oblique, the first, third, 

 and fourth with long forks. 



Differs from P. grandis by the smaller size and the structure of 

 subcosta and cubitus, but is evidently congeneric. P. grandis cam© 

 from an unknown horizon at Fishing Creek Gap, Pennsylvania, in 

 the lower part of the Anthracite series. There is also a hind wing 

 which I refer to P. reticulata. 



E olotype.— C^it. No. 64343, U.S.N.M. 



(2) Blattoid tegmina, representing a new genus. 



COBALOBLATTA, new genus (Archimylacridae). 



Large insects with broad elongated tegmina ; costa convex, rapidly 

 descending to apex, which is either in lowest fork of radius or in 

 interval between radius and media; surface between the veins with 

 very distinct and numerous cross-nervules, which anastomose to form 

 a reticulation, but the general effect is that of very many cross lines, 

 not the distinct polygonal reticulation of Phoherohlatta ; costal area 

 narrower than in Phoherohlatta., only about 3.6 mm. wide at level of 

 first fork of radius ; some of the branches of subcosta forked ; radius 

 with two main divisions, the first with four primary branches above, 

 the first of these branches forking, with each branchlet forking again 

 near margin, the second and third branches forking once; second 

 division of radius forking, with each division again forking, and the 

 first, second, and fourth of the branchlets so formed again forking; 

 media nearly straight, little complicated, its branches essentially bel- 

 low, the main branches two, the second simple, the first forking, and 

 its upper branchlet forking again ; cubical field large and broad, the 

 cubitus rapidly descending, with no appendix; branches of cubitus 

 five, the last forming one side of the short apical fork, the second to 

 fourth once forked, the first forked, with each branchlet again 

 forked ; and area broad and short, with six veins, the second, fourth, 

 fifth, and sixth branched, the fifth with its lower branchlet again 

 branched. 



Type of the genus. — Cohalohlatta simulans, new species. 



