DINOSAURS 177 
centra more or less bi-concave. Many curious features in the 
skeleton can only be explained with reference to the heavy 
(After Marsh.) 
 N@izl 
Fic. 61.—Skeleton of Stegosaurus wngulatus ; length about 25 feet. 
LEAL Ce 
armour of plates and spines with which the Stegosaur was 
N 
