OSTEOLOGY OF THE ARMORED DIHOSAURIA. 



77 



short, but long transversely; deep at the proximal end, with narrow and rounded 

 distal end. 



It will be observed from the above description that the manus of Stegosaurus 

 is entaxonic, as in Diplodocus and Brontosaurus . Digits I and II were doubtless 

 provided with a full complement of phalanges terminating with flattened unguals, 

 which in life were the only external evidence of their presence. In digit? Ill, IV, 

 and V the number of phalanges was probably successively more and more reduced, 

 each being terminated by a short transversely elongated functionless phalanx, 

 that in life was entirely within the mass of the foot. 



Measurements of fore foot elements. 

 METACARPALS. 





I. 



II. 



III. 



IV. 



V. 



No. 

 7401. 



No. 

 4937. 



No. 

 7401. 



No. 

 4937. 



No. 

 7401. 



No. 

 4937. 



No. 

 7401. 



No. 

 4937. 



No. 

 7401. 



No. 

 4937. 





mm. 

 61 



52 



51 

 41 



mm. 

 91 



80 



60 

 75 



mm. 

 84 



49 



50 

 28 



mm. 

 106 



70 



71 

 43 



mm. 

 82 



53 



53 

 28 



mm. 

 126 



78 



78 

 40 



mm. 

 84 



56 



55 

 34 



mm. 

 Ill 



80 



91 

 45 



mm. 

 64 



52 



55 

 35 



mm. 



9S 



72 



79 

 45 



Greatest transverse diameter proxi- 



Greatest transverse diameter, distal 



Least transverse diameter shaft 



PHALANGES, FIRST ROW. 



Greatest length 



Greatest transverse diameter 



Greatest length 



Greatest transverse diameter 



13 



25 

 67 



11 

 39 



20 

 55 



8 

 41 



18 

 '52 







47 













PHALANGES, SECOND ROW. 



51 

 44 



81 

 84 



60 

 46 







































' Estimated. 



Pelvis. 

 Plates 2, 3, and 4. 



The pelvis of Stegosaurus is composed of ilium, ischium, and pubis. These all 

 unite to form the acetabulum, which is quite as well closed by bone internally as in 

 the Ceratopsia. Apparently these elements never coossify as is sometimes the case 

 in the adult members of the Sauropoda and Theropoda. 



Ilium (il.). — The ilium is the largest of the pelvic bones. Its most prominent 

 feature is the great anterior extension and the extreme shortness of the postace- 

 tabular part, which is scarcely one-third as long as the anterior portion. 



The preacetabular process consists of a long, thickened, wide vertical plate of 

 bone, which terminates anteriorly in a rounded truncate end (fig. 42). 



Viewed laterally the superior border of the ilium is curved from end to end, 

 the anterior process being directed outward and downward in the articulated 



