1 82 THE COAL MEASURES AMPHIBIA OF NORTH AMERICA. 



ters based on the fragment. Another species is here added to the genus, based on a 

 portion of a mandible and a portion of the skull. 



The family, Macrerpetidas, may be defined (465) as follows: 



Skull larger than in any other known microsaurian, unless Baphetes proves 

 to be microsaurian; cranial elements sculptured with pits and coarse grooves; 

 lacrimal element present, teeth large, curved inwards and fluted; mandible 

 heavy ; orbits located far back on the skull and near the median line so that the 

 interorbital space is about half the space from the outer edge of the orbit to the 

 border of the skull, thus approaching the condition known in Ervops; the ribs (?) 

 are strong, heavy, and curved, with an incipient tubercle. 



Genus MACRERPETON Moodie, 1909. 



MOODIE, Jour. Geol., xvn, No. i, pp. 72-74, fig. 17, 1909. 



Type: Macrerpeton huxleyi Cope. 



The genus Macrerpeton was proposed for the reception of the amphibian species 

 described by Cope as Tuditanus huxleyi (123). This form he placed provisionally in 

 genus Tuditanus, since it seemed to present the same type of sculpturing of the 

 cranial elements similar to that found in T. radiatus Cope. But this species has 

 been removed from Tiiditanus and placed in a new genus, Erpetosaurus (462). A 

 close study of the type specimen of Tuditanus huxleyi Cope shows (465) great 

 variation and distinction from any of the species described from Linton, Ohio, or 

 indeed from any Carboniferous form thus far known. 



The specimen represents the left side of the face, and the characters exhibited by 

 the fragment are supported by more complete material (No. 2933, Am. Mus. Nat. 

 Hist.). The skull shows a close approach to the higher labyrinthodonts in its shape. 

 The orbits are far removed from the border of the skull. The arrangement of the 

 bones of the skull resembles that of Capitosaurus from the Keuper of Europe. The 

 jaw is for the most part slender, with a pronounced downward inflection at the coro- 

 noidal part. The teeth are heavy and strong and are curved backwards. They 

 have the strong longitudinal fluting which is characteristic of the labyrinthodonts. 

 Another character which is distinctive is the pattern of cranial sculpture. This 

 consists of inosculating 'pits and grooves of a coarse character and compares favor- 

 ably with the sculpturing of Triassic labyrinthodonts. If Macrerpeton really rep- 

 resents a labyrinthodont form of Amphibia it is the oldest of the known Labyrintho- 

 dontidae, since it seems probable that the Eosaurus vertebrae came from a higher 

 horizon. 



Macrepeton huxleyi Cope, 1874. 



COPE, Trans. Am. Phil. Soc., xv, p. 274, 1874. 



COPE, Geol. Surv. Ohio, n, pt. H, p. 397, pi. xxxiv, fig. 2, 1875. 



LESLEY, Dictionary of Fossils, p. 1237, 1890. 



MOODIE, Jour. Geol., xvn, No. I, p. 72, fig. 17, 1909. 



MOODIE, Bull. Am. Mus. Nat. Hist., xxvi, art. xxv, p. 354, pi. lix, fig. i, 1909. 



Type: Specimen No. 119, American Museum of Natural History. Collection of 

 Dr. J. S. Newberry. (Plate 26, fig. 2.) 



Horizon and locality: Linton, Ohio, Coal Measures. 



The first part of the following account of the species, Macrerpeton huxleyi 

 Cope, is a quotation of Cope's description (123) of the type specimen, and the second 

 part deals with the description of the new material. Cope says the species is 



