30 AMPHIBIA AND PISCES OF THE PERMIAN OF NORTH AMERICA 



"Measurements. 



M M 



"Length of the cranium from the Length of premaxillary tooth 0.025 



extremity of the os quadratum. . 0.433 Diameter of premaxillary tooth . . . .007 

 Length of the cranium on middle line .335 Length of posterior maxillary tooth .010 

 Length from end of muzzle to nostril .073 Diameter of median maxillary tooth .007 



Width of cranium between quadrates .306 Length of a dorsal centrum 024 



Width of cranium between epiotics. . .118 Vertical diameter of do 025 



Width of cranium between orbits. . . .086 Vertical diameter of do 025 



Width of cranium at orbits 294 Elevation of neural spine of do 050 



Width of cranium between nares 085 Length of rib on curve 080" 



Diameters of orbits: 



Antero-posterior 048 



Transverse 057 



Revised description: This is contained in the revised description of the 

 genus. 



Eryops reticulatus Cope. 

 Am. Nat., vol. xv, 1881, p. 1020. 



Type: Several small intercentra. No. 4786 Am. Mus. Nat. Hist. Cope 

 Coll. From New Mexico. 



Original description: "The most prominent peculiarity of this species is 

 seen in the neural spines, which are not expanded at the summit, as in E. 

 megacephalus, but have rather contracted apices. Another character is the 

 sharply reticulate sculpture of the maxillary bones. The species is much 

 smaller than the E. megacephalus, or even than the T. insignis, and the 

 extent of the ossification of the vertebral elements is intermediate between 

 the two species. The inferior surfaces of the intercentra are smooth, and 

 the diapophyses are compressed. The occipital condyles are depressed and 

 not very well distinguished inferiorly. The humeri have expanded extremi- 

 ties with enlarged epicondyles, well-developed condyles, and no epitrochlear 

 foramen. Width of occipital condyles, m. 016; elevation of dorsal vertebra, 

 .024; width of intercentrum, .011; length of intercentrum (below), .007; 

 five maxillary teeth in .0x5." 



Revised description: It is impossible to identify the parts used by Cope 

 in this description. This species and Zatrachys apicalis were described by 

 Cope from a mass of clay which contained the mixed remains of several 

 animals. The intercentra seem the only parts which can be identified as 

 having been in Cope's hands when the description was written. The species 

 is very doubtfully to be referred to Eryops, both from its morphological 

 character and its geographical position (see fig. 40, page 109). 



Eryops (?) platypus Cope. 



Icthycanthus platypus, Proc. Am. Phil, Soc, vol. xvi, 1877, p. 574. 

 Eryops platypus, Trans. Am. Phil. Soc, vol. xvi, 1888, p. 289. 



Type: A portion of a skeleton including a front foot. From Linton, Ohio. 



This species was originally described as a distinct type of amphibian, 

 but later referred to the genus Eryops because of its apparent rhachitomus 

 vertebrae and the structure of the foot. It may be a member of Cope's group 

 of the Rhachitomi, but the foot in no wise resembles that of Eryops. It can 

 not be considered a member of that genus. 



