0. C. Marsh—American Jurassic Dinosaurs. 259 
recovered. With such protection as the plates and spines 
together afforded, Stegosaurus was doubtless more than a match 
for his larger brained cotemporaries. 
_ The two known species of Stegosaurus were about thirty feet 
in length. They were herbivorous, and probably more or 
less aquatic in habit. It is possible that the difference between 
Dinosaurs yet discovered. 
he remains of the animals here described are all from the 
Atlantosaurus beds of the Upper Jurassic, in Colorado and 
yoming. In bringing them to light, Messrs. Arthur Lakes, 
W. H. Reed, and §. W. Williston have rendered an important 
Service to science. 
Yale College, New Haven, Feb. 18, 1880. 
