MKRKT.Uf: TRIASSIC TCIIT1I Y( )S.\n;iA. 



15] 



The shaft of the humerus is much shorter than in ('. />< 'In'intH, and is broad- 

 ened by an expansion of tlie anterior margin. The posterior half of the prox- 

 imal end shows a well developed hemispherical articular face which grades 

 into a broad, concave articular face immediately anterior to it. On the ante- 

 rior side of the lower face of the proximal end there is a short but well marked 

 pectoral ridge. On the distal end, the two articular faces are distinctly sepa- 

 rated by a prominent angle. The posterior articular face is much shorter than 

 the anterior. The anterior articular face extends over the anterior distal angle 



Fig. 152. 



lus(t) natans, n. sp. 

 A portion of an an- 

 terior limb, X V->. 



Fig. 153. Mixosaurus 

 cornalianus (Bassani. ) 

 Proximal portion of 

 an anterior limb, 

 X V->. (Adapted 

 from Repossi.) 



. 1.11. Cymbospondylus />r- 

 IriiniM Lc'iily. Proximal 

 portion of anterior limb. 



and along the anterior margin for about three-fourths of the distance to the 

 proximal end. The apparent extension of this face over the anterior border 

 probably represents no more than a cartilage covered surface. The anterior 

 articular face is concave transversely and convex in the direction normal tp the 

 plane of the distal end. The posterior face is convex transversely and concave 

 in the direction normal to the plane of the end. 



To this species the writer is inclined to refer tentatively a small specimen 

 (no. 11229; fig. 152) representing a portion of the epipodial and mesopodial re- 

 gion of a limb, accompanied by a number of rather slender ribs. The epipodial 

 elements appear to be less constricted than in Cymbospondylus petrinus. and 

 have much the same form as Mixosaurus cornalianus. The element which ap- 



