124 E. C. Case — Amyhihian Fauna at Linton^ Ohio. 



Art. XII. — The Environment of the Amphibian Fauna at 

 Linton, Ohio i"^ by E. C. Case. 



The group of vertebrates including amphibians, lisbes, and 

 the probable reptile Eosauravus cojpei, from the Lower Free- 

 port Coal at the old station of Linton in eastern Ohi(> has been 

 known since 1856, when the first description of Pelion lyelli 

 was published by Wyman in this Journal. Since that time 

 papers have been published by Newberry, Cope, Williston, 

 and Moodie, all dealing with the morphology of the animals. 

 A complete bibliography of the subject appears in Moodie's 

 Monograph, The Coal Measures Amphibia of North America,! 

 and need not be repeated here. 



As our knowledge of the taxonomy and morphology of the 

 fauna is now fairly complete, it is possible to turn to a con> 

 sideration of the various factors which influenced their life and 

 development. Fortunately the presence of workable coal in 

 the region has led to a large amount of exploration and exploita- 

 tion of the beds in which the animals occur and it is possible 

 to gain a clear idea of the conditions in which they lived. 



The key to an understanding of this fauna was grasped by 

 Newberry as is shown by the following quotations : 



" In the descriptive portion of this volume, quite a number of 

 species of the fossil fishes from the Coal Measures of Ohio are 

 figured and described. A large part of these are from a single 

 locality, which has already become somewhat celebrated for the 

 number and interest of the fossil forms it has furnished. I refer 

 to Linton, on the Ohio river, at the mouth of Yellow Creek. 

 The fossils are found there in a thin stratum of cannel which 

 underlies a thick seam of bituminous coal, that we have called 

 Number 6, because it is the sixth workable seam from the base of 

 the productive Coal Measures. Already about twenty species of 

 fishes have been obtained from this deposit, and at least as many 

 Amphibians ; and all found here for the first time, although two 

 or three species have since been met with in other localities, in 

 this or adjoining States. On tracing Coal-seam No. 6, in various 

 directions from Linton, the cannel at its base is found to thin out 

 and soon disappear. We learn, from a careful study of the 

 deposit, that there was in this locality at the time when the coal 

 was forming, an open lagoon, densely populated with fishes and 

 salamanders ; and that after a time this lagoon was choked up 

 with growing vegetables ; and peat (which afterward changed to 

 cubical coal) succeeded to the carbonaceous mud (now cannel) 



*This paleogeograpliic study is published by permission of the President of 

 the Carnegie Institution of Washington. 



t Moodie, R. L., Publication 538, Washington, 1916. 



