OSTEOLOGY OF THE AEMOKED DINOSAUEIA. 



81 



although there is a faint constriction connecting it with the shaft of the bone as in 

 Diplodocus. The great trochanter is not separated from the head, hut as in the 

 Sauropodous dinosaurs the rugose proximal surface of the latter continues un- 

 interruptedly and covers the superior surface of the great trochanter. The head of 

 the femur of Stegosaurus prisons Nopcsa is strikingly different from any of the American 

 forms, in having a distinct head and an elevated trochanter major. 1 In these 

 respects it resembles Triceratops more nearly than Stegosaurus. 



-A 



Fig. 45. — Comparative views of Stegosaurus femora. Viewed from the front. All & nat. size. (1) Femur 

 of s. ungulatus marsh, cotype. yale museum. (2) femur of s. altispinus gllmore. type. university of 

 Wyoming Collection. (3) Femur of S. stenops Marsh. Type. No. 4934 U.S.N. M. a, lesser trochanter; 6, greater 

 trochanter; h, head. 



In the collections of the National Museum there are 10 Stegosaurian femora, 

 but on none do I find a rugose area extending down any appreciable distance on the 

 superior external surface, such as noted by Osborn 2 in Diplodocus, although on some 

 specimens there is a rugose area running down on the outer anterior surface as in 

 Mastodon and ElepTias. 



A small finger-like proximal or lesser trochanter, called great trochanter by 

 Owen in Iquanodon, is present in S. stenops (3, fig. 45. a.) and on all the other femora 



1 F. Baron Nopcsa, Geol. Magazine, vol. S, No. 4, 1911, p. 147, fig. 6 (c). 

 * Mem. Amer. Mus. Nat. Hist., vol. 1, pt. 5, 1S99, p. 211, fig. 14 (o), tr. I. 



