78 Br. J. S. Newberry on American Fossil Fishes. 



In addition to the fishes of the Coraiferous limestone enumer- 

 ated in the preceding pages, fragments of the armor of large Pla- 

 coderm Ganoids have been found which have been referred to 

 Coccosteus and Cephalaspu, but more and better specimens will 

 be necessary to prove that these genera were represented in our 

 Devonian seas. A number of placoid spines and teeth have also 

 been taken from the Cliff limestone of Ohio, which have not yet 

 been described. 



In the upper members of the Devonian formation, the num- 

 ber of fossil fishes yet discovered in this country is small. A 

 species of Palceoniscm obtained by Prof. Brainard from the Port- 

 age group in northern Ohio, (P. Brainardi) • two species of Ho- 

 hptychius from the Catskill of New York, another with a placoid 

 spine from the same formation in Pennsylvania, complete the 

 catalogue. 



Of these the Pakeonisciis, described by Mr. Thomas, is appa- 

 rently a good species, and is interesting from its antiquity. The 

 two New York species of so-called Holoptychius have, I believe, 

 never been critically examined, and it is by no means certain 

 that they are such. That described by Dr.' Leidy from Penn- 

 sylvania is a well marked species of this genus, evidently closely 

 allied to H. nobilissimvs of Europe. 



It will be noticed in the foregoing sketch that no mention is 

 made of many of the most characteristic genera of fishes of the 

 Devonian rocks of the old world, and up to the present time we 

 have no proof that any of the Placoderms, Asterokpis {Pterichthys 

 of Miller), Coccosteus, Cephalaspis, Pteraspis, &c., of the Coela- 

 canths, Homostius {Asterokpis of Miller), Bothriolepis, Dendrodns, 

 Psammosteus, &c., of the Dipterians, Dipterus, Osieolepis, Diplop- 

 terus, &c., or the Acanthians, Acanthodes, Diplacanihus, Cheirole- 

 pis^&Q. ever had any existence in America, 

 ridence c 

 ' all be 1 



id many species are common to the two continents, the fishes | 

 far as known are all specifically distinct, and the larger part g 

 of them generically different. 



The evidence on this point is of course as yet only negative, 

 and may all be soon reversed, but it is nevertheless rather re- 

 markable that while most of the Devonian molluscous genera, 



