ART. 18 AGE OF NORTH AMERICAN TRIASSIC BEDS VON HUENE 



9 



criticism of the geological portion of this paper, which he so kindly 

 furnished me. 



(1) Typothorax coccirMrum Cope. Right femur in yellow sandy 

 clay, from near Tanners Crossing, Ariz. The proximal extremity 

 has a surprisingly large trochanter minor. Trochanter quartus and 

 distal end are the same as in Cope's type ^^ from New Mexico. It 

 probably also belongs to the Upper Trias as in New Mexico. (Cat. 

 No. 5784, U.S.N.M.) 



(2) Parasuchian bones. There are a number from Tanners Cross- 

 ing, Ariz., belonging to the Middle Triassic fauna. Among these is 

 a good interclavicle (Cat. No. 2153, U.S.N.M.), a fair humerus (Cat. 

 No. 2154, U.S.N.M.), a complete ulna (Cat. No. 2154, U.S.N.M.), 

 and a femur lacking only the distal end (Cat. No. 2163, U.S.N.M.). 



Figs. 6-8. — 6, Probably right astragalus of a Parasuchian. Middle Texas from 

 'NEAR Tanners Crossing, Littlh Colorado Valley, Ariz. U. S. Nat. Mus. No. 2160, 

 a, from above, h, lateral view, o, from below. 7, Dorsal vertebra of a 

 Stegocephahan (Metoposaurid), same locality. U. S. Nat. Mus. No. 2158, a, 



FROM in front, h, FROM RIGHT SIDE. 8, CADDAL VERTEBRA OF A STBGOCEPHALIAN 



(Metoposaurid). U. S. Nat. Mus. No. 2158, a, from below, b, from behind, c, from 

 LEi'T side. All figures 1 : 2 nat. size. 



One of these bones could possibly be an astragalus ; if so, it is the first 

 known Parasuchian astragalus. It is flat, rounded below, and blunt 

 on the lateral side. Above it is excavated along the anterior border 

 in a narrow strip, and the larger posterior part forms a curved ele- 

 vation. From the known distal end of the tibia ^- this form of 

 astragalus was to be expected. It would fit better with Episcopo- 

 saurus than with Phytosaurus or Mystriosuchus (Cat. No. 2160, 

 U.S.N.M.). 



2» See Bull. Amer. Mus. Nat. Hist., vol. 34, 1915, p. 485 and following. 

 2* Idem., p. 494. 



