no 
EXTINCT MONSTERS. 
Evolutionist of to-day leads the doubting brother across the 
shallow remnant of the gulf, once thought impassable.” ^ 
We now pass on to describe two of the strangest and most 
wonderful of all the Dinosaurs, recently discovered in the far 
West. The first of these is the Stegosaurus,^ or plated lizard, 
not wholly unknown before, because part of its skeleton was 
found some years ago in a brickfield in the Kimmeridge Clay 
at Swindon. It has been proved that some of the bones to which 
the name Omosaurus^ has been applied really belonged to the 
former genus. 
With such complete specimens now known by Professor 
Marsh’s descriptions, it will not be necessary to mention the 
meagre remains discovered in this country, or the conclusions 
arrived at by Owen and Seeley, interesting as they are. 
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; 
they 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 Atlantosaurus. 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. 25 shows the skeleton.) ^ 
In 1879 Professor Marsh announced the discovery of additional 
^ The Introduction and Succession of Vertebrate Life in America. An 
address delivered before the American Association for the Advancement of 
Science, at Nashville, Tenn., August, 1877. See Nature^ vol. xvi. 
^ Greek — stegos, roof or covering ; sattros, lizard. 
® Greek — omos, humerus, and satiros, lizard. 
^ The writer is informed that this skeleton is not yet mounted in the 
Yale College Museum, but that it will be before long. Our artist has drawn 
it as if set up, with a man standing by for comparison. 
