3o8 Evolution and Distribution of Fishes 



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 No. 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." 



Cope in subsequently describing these amphibians says 

 of the deposit: "They occur in a small basin near the 

 middle of the series, in the lower part of the 'diamond 

 bed.' This is eight feet in thickness and the fossil batrachia 

 and fishes are found on the slate, which is in contact with 

 the lower three to six inches of the seam, which is cannel 

 coal." As to its mode of origin, Newberry says: "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 

 vegetation; and peat (which afterwards changed to cubi- 

 cal coal) succeeded to the carbonaceous mud (now cannel), 

 that had previously accumulated at the bottom of the 

 water. The fishes of this pool were mostly small tile- 

 scaled ganoids, belonging to the genus Eurylepis. Though 

 here extremely abundant, they have not been found else- 

 where. . . There were also in this lagoon two or per- 

 haps three species of Coelacanthiis (one of which is so 

 closely allied to C lepturtis of the Coal Measures of Europe, 

 that they should perhaps not be separated) and yet this 

 genus has been nowhere else recognized on the American 

 continent. There are also found here the thin scales, from 

 one to two inches in diameter, some ornamented and some 

 plain, and also the lance-head teeth of Rhizodus, and the 

 teeth and spines of Diplodus." It is worthy of passing note 

 here that C. elegans (C. lepturtis) is specifically the same as 

 that reported from England and Scotland. 



In proceeding from the Carboniferous to the Permian 

 rocks Megalichthys and Coelacanthiis still persist, for Cope 

 has described two species under the name Ectosteorhachis 

 {Parahatrachus of Owen) from the Permian of Texas; 

 while Coelacanthiis graniilatus has been found in the Upper 



