268 



SUPPLEMENT 'J'O THE EXTINCT BATPtAClIlA 



OESTOCEPHALUS EEMEX, Co^^e. 

 Transac. Amer. Philos. Soc, XIV, 18(39, p. 17. 



OESTOCEPHALUS RECTIDEXS, Cope, Bp. Nov. 



Indicated by a left dentavy bone with its teeth and external surface preserved. The latter is nearly smooth 

 and without sculpture. The outer face is convex, and the general form is slender, but not curved upwards at the 

 extremity. Teeth straight and conic, apex acute ; no visible grooves of the surface ; eleven in m. .005, closely 

 placed, and of equal lengths. The extremity of the dentary does not exhibit teeth, but they may be concealed. 



M. 



Length of dentary, .. • 0.023 



" tooth line, * .0152 



Depth dentary at last tooth, ' . .0027 



This represents a smaller animal than does the skull of 0. curvidens, and differs much from the latter in the 

 more closely placed and perfectly straight teeth. 



I describe here a sijecimeu which is closely related as to size to the 0. rcct.idens, and is probably a member 

 of this genus ; but the specific reference will remain uncertain till other portions of the- skeleton are discovered. 

 Those preserved consist of twenty-five caudal vertebr.TB, probably from the anterior part of the column. There ai-e 

 therefore no ribs nor ventral armature. The centra are rather elongate and expanded at the extremities. The neural 

 arches have a close union. There are no diapophyses, but the fan shaped and striate neural and basmal spines are 

 present. They are, however, shorter thafi in 0. remcx, and not so expanded as in the species of Ptyonius. The 

 bases aie quite narrow. Their reduced size may be derived from the following measurements. Length of three 

 centra, m. .0086 ; extent of neural and haemal spines, .0087. The same dimensions in 0. remex are .012 ; extent of 

 spines, .02. While this species is smaller than the latter, it is larger than any known Ptyonius, its elongate vertebras 

 are most like those of Oestocepftalus. 



BRACHYDECTES, Cope 

 Proceed. Acad. Nat. Sci., Philadelphia, 1868, 214. Transac. Amer. Philos. Soc, 1868, XIV., p. 14. 



This geims is indicated by two rami of a mandible and a portion of a premaxil- 

 lary only. These, when compared with those of Oestocejjlialus and Dendreiyeton, 

 from the same locality, and with others described by authors, are so much stouter, i. e., 

 shorter and more elevated, that they evidently belong to a peculiar genus. The 

 genus further differs from O'estoceplialus in having the teeth of equal size to the 

 posterior parts of the series, that is, to the base of the elevated coronoid process. 

 The teeth are elongate cylindric cones, with their acute tips turned a little poste- 

 riorly. The fractured ones display a large pulp cavity. The three premaxillaries 

 preserved are similar, but without curvature of the tips. They do not exhibit striae 

 or any other sculpture. 



So far as the remains known go, the genus is nearer Hylerpeton than any other. 

 According to Dawson that genus is provided with a large canine-like tooth, at the 

 anterior extremity of the maxillary, on the inner row, which is inserted into a dis- 

 tinct socket. jN'o such tooth appears among those of this genus. The latter does 

 not give any indication of the very elevated coronoid process of Bracliydectes, though 



