THE PERMIAN FISHES OF NORTH AMERICA 171 



It was at once pointed out by Newberry that the material representing this 

 genus was "too imperfect for satisfactory study" and that it represented 

 an amphibian and not a fish.* 



In 187s Cope emended his description, published a figure of the type, 

 and gave his grounds for regarding the species as fish and not amphibian.f 



Fig. S4- — Sphcerolepis arctata (Cope). X a. 



A. Fragment of a palatal (?) plate, bearing 

 denticles. No. 7932 Am. Mus. 



B. Fragment of mandible or maxilla, bearing 

 relatively large conical, partly striated teeth. 



C. Specimen shown in A, in side view. 



But it is evident, on even little study, that neither his figure nor his diag- 

 nosis offers any distinctive characters by which one could recognize this 

 genus in a lot of material. Some of the characters he enumerated were 

 undoubtedly derived from a specimen of Coelacanthus which, as appears 

 from his figures, had become mixed up with his type specimen. J 



For these reasons Peplorhina is to be looked upon as an insufficiently 

 defined genus, and Sphcerolepis Fritsch should be substituted, 



SphEerolepIs arctata (Cope). (Plate 31, figs. i-2a, text fig. 54.) 



1877. Peplorhina arctata Cope, Proc. Amer. Philos. Soc, p. 54. 



1882. Theromorphus saurian Cope, Proc. Amer. Philos. Soc, p. 461, footnote. 



1891. Peplorhina arctata Cope, Woodward, Cat. Fos. Fishes, 11, p. 408. 



1900. Peplorhina arctata Cope, Case, Journ. Geol., viii, p. 707. 



Type: A fragmentary dentigerous plate. No. 65 1 1 University of Chi- 

 cago. Vermilion County, Illinois. 



Referred specimens: 



1. A small symmetrical element bearing similar teeth and from 



the same locality as the type. No. 65 1 2 University of Chicago. 



2. A fragment of a larger palatal (J) plate than either of the two 



preceding specimens, bearing similar teeth. Texas. Collected 

 by Dr. E. C. Case. No. 7932 American Museum. 



3. A small fragment of a mandible or maxilla bearing relatively 



large conical teeth, which are striated in their lower half. 



Original description of species: "The bone is plate-like and diamond- 

 shaped, with the longer angles both recurved. The convex surface is thickly 

 studded with teeth which are not in contact with each other. Their size 

 increases from one side of the bone to the other, and still more, from one 

 extremity to the other. The crowns are swollen at the nearly sessile base, 

 and contract rapidly to a conical and unsymmetrical apex. Those of the 

 smaller teeth are more conical, those of the larger more bulbiform. One 

 side of the latter is slightly concave below the apex. The surface is shiny 

 and distinctly grooved. Fractured crowns do not display any central 

 cavity. There are sixty-five teeth on the plate. 



* Proc. Acad. Nat. Sci., Phila., 1873, p. 426. 

 t Geol. Sur. of Ohio, 11, pt. ii, Palseont., p. 409. 

 t Ibid., pi. zlii, fig. 4. 



