120 G. B. Wieland — Notes on the Armored Dinosauria. 



to the fortunes of collection, the bony plates thus far found 

 more or less closely associated with the reptiles of the Ceratops 

 beds do not represent the true abundance and proportion of 



Fig. 5. 



sn 



sn 



Figure 5. — Rounded, elliptical and subrhombic dermal plates of Nodo- 

 sauridae or Ceratopsidas, further illustrating the great variety of form and 

 the changing development and position of the spinal node. All are from 

 the Ceratops beds of Converse County, Wyoming, and at least in part 

 from the same individual as the plates shown in figure 4. 



i-v form a series passing from a rounded flattened tubercle (i) to a form 

 with a low node (n), to a ridded form (in), and then a form with a heavy 

 spinal node sn (iv). In v the spinal node sn lies near to the posterior border. 



All are of heavy and comparatively dense bone, upper surfaces usually 

 showing nutrition canals. 



armored saurians in that horizon. Such armor is as a rule 

 found at some distance from the skeletons to which it belongs, 

 and yet it caunot serve as a satisfactory basis for new species. 

 There may, therefore, be far more of it in the various collec- 



