Nodosaurus textilis Marsh. 113 



The largest fragment belongs to the right scapnla, and is 

 massive, with a curved extremity. The lateral margins 

 are roughly parallel and the bone is not only curved m 

 two dimensions but twisted as well, as though it fitted 

 closely over the curved ribs. It resembles, in so far as 

 a comparison can be made, that of Ankylosaurus (Brown, 

 1908, fig. 15), but has about three fourths the dimensions 

 of the latter. 



Measurements of Scapula. 



mm. 



Width at extremiity 172.5 



Thickness 33 



Max. thickness of fragment 49.5 



Humerus. — Several fragments which are believed to 

 pertain to the humerus are present, but are inconclusive 

 and not worthy of description. They do, however, give 

 a check on relative proportions (see restoration, fig. 7). 



Radius and ulna (pi. IV, figs. 2, 3; text fig. 4). — The 

 proximal ends of the right radius and ulna, and a portion 

 of the left ulna, are present and are typically stegosaurian 

 or ceratopsian and totally unlike those of any other 

 dinosaurian group. The olecranon process is very 

 massive and extends considerably beyond the humeral 

 articulation. The humeral facet, however, covers about 

 half of its anterior face. The radial facet is a clearly 

 defined depression and gives the bone a triangular cross- 

 section at that point, with two hollow faces. The 

 articular face, as with the femur and tibia, had a 

 smoother, more finished appearance than in the Stego- 

 saurus specimens I have seen. Proximally and exter- 

 nally the grain of the bone is coarse. 



The radius shows an ovate cross-section in the shaft, 

 but is somewhat more irregular in outline at the expanded 

 proximal end. The proximal face bears a circular 

 saucer-shaped depression, whereas in Stegosaurus such 

 a depression is barely discernible. The difference may 

 be due to the relatively thick articular cartilage in the 

 latter as compared with that of Nodosaurus , as indicated 

 by the rugose character of the articular ends in Stego- 

 saurus. Aside from this and certain proportional distinc- 

 tions, the resemblance of Nodosaurus to Stegosaurus in 

 these elements is quite marked. The elbow must have been 

 very readily flexed and carried in a partially bent 



Am. Jour, Sci.— Fifth Series, Vol. I, No. 2.— February, 1921. 



8 



