i8o 



EXTINCT MONSTERS 



a somewhat different representation of the Stegosaur, in which 

 the length of the hind limbs is more apparent, and also they are 

 more free from the body. 



Finally, the Stegosaur displays a rather remarkable feature; 

 for a very large chamber was found in the sacrum l formed by 



FIG. 64. 1, 2. Plates of Stegosaurus. The middle figures show their thickness. 



(After Marsh.) 



an enlargement of the spinal cord. 



The next monster to be described is one that has fortunately 

 left to posterity a good record of itself, and probably was 

 not very unlike the Hylseosaurus of Mantell. This is the 



1 The sacrum may be thus denned : the Vertebrae (usually fused together) 

 which unite with the haunch-bones (ilia) to form the pelvis. 



