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Page:Popular Science Monthly Volume 72.djvu/568

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POPULAR SCIENCE MONTHLY

been of terrestrial habits, and Dawson frequently speaks of them as "lizard-like" and his restorations of some of the forms, though based on very scanty remains, indicate forms which would be taken for modern lizards. While his restorations are in part fanciful, he has given, in the main, an accurate idea of the animals as indicated by the remains preserved in the old stumps of the swamp in which the animals lived.

Cope's researches into the structure of the early quadrupeds constitute an interesting chapter in the history of the early vertebrates. His researches on the extinct Amphibia began in 1865 by the publication of the description of the form known as Amphibamus grandiceps, from the Mazon creek beds of Illinois. This specimen was loaned to the Illinois Geological Survey for Professor Cope to study by Mr. Joseph Even of Morris, Illinois. After Cope's description of the form, the specimen was returned to Mr. Even and, as Mr. L. E. Daniels tells me, it was later destroyed by fire. Mr. Daniels has recently been kind enough to allow me to study a specimen of this form in his collection, the only one, so far as I am aware, now in existence (Fig. 3). The peculiar characters of this form are the possession of sclerotic plates in the eyes and the possession of long curved ribs which have been recently described by Dr. Hay from this same specimen. A specimen of another species from his same deposit has been in the Gurley collection for nearly thirty years. Dr. Newberry saw it when he studied Mr. Gurley's fishes and said in a note that Professor Cope should see it. It was never sent to Cope, however, and it is described elsewhere by the writer as Micrerpeton caudatum, gen. et sp. nov. This is a very interesting form, since it shows the impression of the fleshy tail (Fig. 4). On this tail impression are preserved many important structures heretofore unknown for the Branchiosauria to which the form belongs. As such it represents not only the earliest geological evidence of the group, but it is the first appearance of the Branchiosauria in the discoveries in the early quadrupeds in North America. It is a typical branchiosaurian and as such belongs to the family in which the Branchiosaurus of Europe is placed.

Between the years 1865 and 1897 Cope continued his investigations on the early quadrupeds and his results are to be found in the proceedings of several learned societies. He early recognized the unusual characters of the Carboniferous fauna, and his many papers attest his interest in the forms which constitute it. He has described all but two of the known Carboniferous species from the deposits of the United States. Among the many peculiar types of amphibians described by Cope none is more bizarre than the form from the Permian of Texas known as Diplocaulus magnicornis Cope. This peculiar form has been widely described and commented on. Its affinities are clearly with the Microsauria, and it is one of the latest representatives of that group