PAE MOCNITEDESKELETON, OF BRON TOSAURUS. (67 
braces and buttresses of thin bony plates connecting the broad 
articulating surfaces and muscular attachments, all the bone 
between these thin plates being hollowed into a complicated 
FIG. 8. MODEL OF BRONTOSAURUS. BY CHARLES R. KNIGHT, 1905 
Executed from the mounted skeleton, under direction of Professor H. F. Osborn 
system of air-cavities. This remarkable construction can be 
best seen in the unmounted skeleton of Camarasaurus, another 
Amphibious Dinosaur. 
The teeth of the Brontosaurus indicate that 1t was an her- 
bivorous animal feeding on soft vegetable food. Three opinions 
as to the habitat of Amphibious Dinosaurs have been held by 
scientific authorities. The first, advocated by Professor Owen, 
who described the first specimens found forty years ago, and 
supported especially by Professor Cope, has been most generally 
adopted. This regards the animals as spending their lives en- 
tirely in shallow water, partly immersed, wading about on the 
bottom or, perhaps, occasionally swimming, but unable to 
emerge entirely upon dry land. More recently Professor Osborn 
has advocated the view that they resorted occasionally to the 
land for egg-laying or other purposes, and still more recently 
the view has been taken by Mr. Riggs and the late Mr. Hatcher 
that they were chiefly terrestrial animals. The writer inclines 
to the view of Owen and Cope, whose unequaled knowledge of 
comparative anatomy renders their opinion on this doubtful 
question especially authoritative. 
The contrast between the massive structure of the limb-bones, 
ribs and tail, and the light construction of the backbone, neck 
