72 



PERMO-CARBONIFEROUS VERTEBRATES FROM NEW MEXICO. 



Edaphosaurus — Continued. 

 Edaphosaurus pogonias Cope, Proc. Amer. Phil. Soc, xx, 1882, p. 448; Trans. Amer. Phil. Soc, XVli, 



1892, p. 15, pi. xi, ff. 5, 5a. Case, op. cit., 1907, pp. 69, 151, pi. xxxiv. 

 Edaphosaurus microdus Cope, Proc. Amer. Phil. Soc., xxii, 1884, p. 37. 



Naosaurus microdus Cope, Amer. Nat., xx, 1886, p. 544; Trans. Amer. Phil. Soc, xvi, pp. 287, 

 295. Case, op. cit., 1907, p. 61. 

 Edaphosaurus claviger Cope. 



Naosaurus claviger Cope, Amer. Nat., xx, 1886, p. 544; Trans. Amer. Phil. Soc, xvi, 1888, pp. 

 287, 293, pis. ii, iii. Case, op. cit. pp. 59, 139, pis. xxviii, xxix, xxx, 1907. 

 Edaphosaurus cruciger Cope. 



Dimetrodon cruciger Cope, Amer. Nat.,xxi, 1878, p. 829; Proc. Amer. Phil. Soc, xix, 1880, p. 44. 

 Naosaurus cruciger Cope, Amer. Nat., xx, 1886, p. 544; Case, op. cit., 1907, pp. 60, 146. 

 Edaphosaurus novomexicanus Williston and Case, infra. 



Until the material described in the present paper was discovered, the type 

 specimen of Edaphosaurus pogonias preserved in the American Museum was the 

 only one of the genus confidently known. This specimen, unfortunately, was so 

 crushed in fossilization that its true characters were very difficult to determine; 

 attempts to restore it by Case and Broom were only in part successful, as will 

 be seen. 



In the summer of 1910, Mr. Paul Miller was so fortunate as to discover, on 

 Moonshine Creek, in Baylor County, Texas, probably from the lower Clear Fork 



Fig. 46. — Skull of Edaphosaurus ? pogonias (Cope) Williston and Case. No. 625, University of Chicago, 

 X %. A, from the left side, a, section of the jaw; B, from above; C, from behind, ang, angular; fr, 

 frontal; /, lachrymal; m, maxilla; n, nasal; pa, parietal; pfr, prefrontal; pof, postfrontal; pi, pterygoid; 

 sq, squamosal; sur, surangular; po, postorbital; oc, occipital condyle. 



beds, an excellent skull referable with certainty to Edaphosaurus, but whose pre- 

 cise specific determination is impossible at the present time. From E. pogonias it 

 seems specifically different in the proportions and shape of the bones of the upper 

 side, and, as the skull is quite unknown in the other described species, it may be a 

 long while before its specific identity is certainly proven. In much probability 

 some one or another of the three species, E. claviger, E. cruciger, and E. microdus, 

 is identical with E. pogonias, and the giving of a new specific name to the present 

 specimen, while temporarily convenient, would in the end probably encumber the 

 synonymy to a still greater extent. This species, until more is known of the allied 

 ones, may be known as E. ? pogonias Williston and Case. Comparisons of the 

 specimen will be made in the discussion of the following species, E. novomexicanus, 

 the skull of which seems more nearly like that of the type. 



The skull (fig. 46) as a whole is very high, narrow, and short, subquadrilateral 

 in shape, less deep in front, with the nasal region convex. Its greatest width above 



