DINOSAURS 183 
the present day. Twenty different skulls of this kind have been 
found, and Professor Marsh places the horned Dinosaurs in a 
separate family, to which he has given the name Ceratopside, or 
horn-faced. Their remains come from the Laramie beds, believed 
to be of Cretaceous age, but representing a remarkably mixed fauna 
and flora, so that some have considered them to be Tertiary. The 
strata containing these fossils are very rich in organic remains, 
and have yielded not only other Dinosaurs, but Plesiosaurs, 
crocodiles, turtles, many small reptiles, a few birds, fishes, and 
small mammals. The Ceratops beds are of fresh-water or brackish 
origin, and can now be traced for nearly eight hundred miles 
along the east flank of the Rocky Mountains. 
In this Dinosaur we find the fore feet larger than usual in 
proportion to the hind limbs, and there can be no doubt that it 
walked on all fours. Its length was about 19 feet 8 inches. The 
original estimate of Professor Marsh was about 25 feet, but 
Mr. Gilmore, who made the model shown in Plates X XVII. and 
XXVIII, has taken out six vertebre so that the length is now 
reduced to 19 feet 8 inches. All the vertebre and limb-bones 
are solid. The brain was smaller in proportion to the skull 
than in any known vertebrate. 
The teeth are remarkable in having two distinct roots. The 
wedge-like form of the skull is also very peculiar. The two large 
horns come immediately over the eyes, and the small one above 
the nose; this Dinosaur was, therefore, well provided with 
weapons of offence, such as would be highly useful in driving 
away or wounding carnivorous enemies, The back part of the 
skull rises up into a kind of huge crest, and this during life was 
protected by a special fringe of bony plates. Such an arrange- 
ment doubtless formed an effective shield to ward off blows when 
one Triceratops was fighting another, as bulls or buffaloes of the 
