CHAPTER XXIII. 



SUPPOSED M1CROSAURIAN SPECIES OF UNCERTAIN RELATIONSHIP. 



The following three species are so unusual and so incompletely known that they 

 can not be considered with any of the above families: Brachydectes newberryi Cope, 

 Linton, Ohio; Amblyodon problematicum Dawson, Nova Scotia; Proterpeton gurleyi 

 Moodie, Danville, Illinois. 



Genus BRACHYDECTES Cope, 1868. 



COPE, Proc. Phila. Acad. Nat. Sci., 1868, p. 214. 



COPE, Trans. Am. Phil. Soc., 1868, p. 14. 



COPE, Geol. Surv. Ohio, II, pt. H, p. 388, 1875, pi. xxvii, fig. 2. 



Type: Brachydectes newberryi Cope. 



Cope (Geol. Surv. Ohio, vol. n, pt. II, p. 388, 1875), says: 



' ' This genus is indicated by two rami of a mandible and a portion of a premaxillary only. 

 These, when compared with those of (Estocephalus and Tuditanus, 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 genus unlike either. The genus further differs from (Esto- 

 cephalus in having the teeth of equal size to the posterior part of the series ; that is, to the 

 base of the elevated coronoid process. The teeth are elongate cylindrical cones, with their 

 acute tips turned a little posteriorly. The fractured ones display a large pulp cavity. The 

 three premaxillaries preserved are similar, but without curvature at 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 distinct socket. No 

 such tooth appears among those of this genus. The latter does not give any indication of 

 the very elevated coronoid process of Brachydectes, though the external portion of the 

 dentary bone in that region being lost, little can be said about it." 



Brachydectes newberryi Cope. 



COPE, Proc. Phila. Acad. Nat. Sci., p. 214, 1868. 



COPE, Trans. Am. Phil. Soc., 1868, p. 14. 



COPE, Geol. Surv. Ohio, n, pt. n, p. 388, pi. xxvii, fig. 2, 1875. 



Type: Specimen No. 8604 G, American Museum of Natural History. 



Horizon and locality: Linton Ohio, Coal Measures. 



Cope (Geol. Surv. Ohio, vol. n, pt u, p. 388, 1875) says of this form: 



" The species is represented by one nearly perfect ramus mandibuli, one dentary bone 

 and one premaxillary, probably not complete. 



" The dentary bone appears to have been attached by suture to the articular and angular, 

 as its free margin has very much of the outline of that suture in Amphiuma and lizards. The 

 coronoid process would also seem to be a part of the same bone as in Amphiuma and Meno- 

 pcma, and not composed of the coronoid bone as in lizards. It rises immediately behind the 

 last tooth, and displays no suture. 



'75 



