OSTEOLOGY OP THE AEMOEED DINOSAURIA. 



81 



although there is a f amt constriction connecting it with the shaft of the bone tis in 

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

 Sauropodous dinosaurs the rugose proximcl 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 strildngly different from any of the American 

 forms, m having a distinct head and an elevated trochanter major.' In these 

 respects it resembles Triceratops more nearly than Stegosaurus. 



-A 



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



OF S. UNQULATUS MARSH. COTYPE. YALE MuSEUM. (2) FeMUR OF S. ALTISPINU3 GlLMOEE. TYPE. UNIVERSITY OF 



Wyoming Collection. (3) Femur of S. stenops Mar.sh. T^te. No. iM4 U.S.N.M. a, lessee trochanter; b, greater 



trochanter; h, HEAD. 



In the collections of the National Museum there ai-e 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 ' in Diplodocus, although on some 

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

 Mastodon and Elephas. 



A small finger-hke 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 



' F. Baron Nopcsa, Ceol. Magazine, vol. S, No. 4, 1911, p. 147, fl?. 6 (c). 

 " Mem. Amer. Mus. Nat. Hist., vol. 1, pt. 5, 1«99, p. 211, fig. 14 (a), tr. I. 



