176 EXTINCT MONSTERS 
In the year 1877 Professor Marsh described, in the American 
Journal of Science, a considerable portion of a skeleton of a 
Stegosaur, remarking that this genus proved to be one of the 
most remarkable animals yet discovered. It was found on the 
eastern flank of the Rocky Mountains, in strata of Jurassic age ; 
the bones indicated an animal about twenty-five feet long, and for 
this discovery Science is indebted to Professor A. Lakes and 
Engineer H. C. Beckwith of the United States Navy, who found 
the remains in Colorado, near the locality of the gigantic Atlanto- 
saurus. The solid limb-bones seem to point to an aquatic life, 
but there can be little doubt that the monster did not pass all 
its time in the water. (Fig. 61 shows the skeleton.) 
In 1879 Professor Marsh announced the discovery of additional 
remains from several localities. The most striking feature—from 
which the Stegosaur takes its name—was the presence of huge 
bony plates belonging to its skin, as well as large and small 
spines. Some of the plates were from two to three feet in 
diameter, and they were of various shapes. Of the spines, some 
were of great size and power, one pair being each over two feet 
long! The skull was remarkably small, and more like that of a 
lizard than we find in most Dinosaurs; the jaws were short and 
massive. Little was known at first of the brain, but fortunately 
a later discovery showed the brain-case well preserved. Later 
still, more than twenty other specimens of the Dinosaur were 
obtained, so that nearly every portion of the skeleton is now 
known. The skulls indicate that the creature possessed large 
eyes and a considerable power of smell. The jaws contain but 
a single row of teeth in actual use; but as these wore out, they 
were replaced by others lodged in a cavity below. Teeth, how- 
ever, were not its strong point; they indicate a diet of soft 
succulent vegetation. The vertebre have the ends of their 
