The above five insect remains, claiming affinity with the modern genus Gryllacris, of the order Orthoptera, retain for the investigator no characters in common, but such as may be afforded by the central portion of the principal disk or internomediate field of the elytron, and by the lesser marginal field. From comparison of these areas in the specimens from the Coal-measures, as regards configuration and venation, a certain similarity of design is observed, and a general correspondence detected. By taking Heer's descriptions and figures as data, this character is seen to be reproduced—less markedly distinct from the type observable in certain species of the modern genus of Burmeister—both in the profile of G. Ungeri and in other fragments preserved to us in the Eocene strata of the Continent. Complete identification of these species must be the reward of future investigators.