Jan., 1892. 
DRAGONS OF THE PRIME. 
5 
we can tell that lie was a plant-eater, and lived on the vege¬ 
tation of the countrv. 
«/ 
But if Ceteosaurus was big, his near relative, Atlantosaurus , 
was huge enough to make three of him. Atlantosaurus was 
100ft. long, and 40ft. high, yet a harmless creature withal, 
which would only take flesh-food if an animal happened to 
get entangled amidst the bushes of the forest which he was 
engaged in masticating. 
Some of the Dinosaurs, then, closely resembled ordinary 
reptiles in their mode of walking on all fours; others, however, 
as I said, touched the ground with the front limbs only seldom, 
or not at all, walking on the hind limbs with the body semi- 
erect, and partially supported by the tail, as in the kangaroos. 
Such an animal was Iguanodon. The evidence for the idea 
that these Dinosaurs used their hind limbs alone for pro¬ 
gression is as follows :— 
(1) .—Foot-prints have been found which correspond to the 
toes of the hind feet; they always exist in single pairs, as do 
those of birds, and no prints are found in connection with 
them which would correspond to the front feet. 
(2) .—Their front limbs are both much shorter than the 
hind limbs, far too short to touch the ground, and keep the 
body horizontal. And also are very weak, while the hind 
limbs are stout and strong. 
These reptiles, then, have given up the horizontal position 
of the body and the mode of progression usual to their order, 
and have taken to that characteristic of birds; with the 
assumption of this semi-erect position, and of this movement 
confined to the hind-limbs, modifications in the arrangement 
of the bones of the latter and of the pelvis appear very like 
that in birds. 
Just as in birds, the body of these Dinosaurs (Fig. 4) is 
balanced on a horizontal axis passing through the upper ends 
of the thigh bones and the sockets of the pelvis, and also, just 
as in birds, the fore-part of the body is the heavier, and is 
prevented from falling forward by a similar arrangement of 
bones and muscles. This is seen on comparing the pelvis 
of the Dinosaurs with that of a bird, say of one of the group 
of Ostricli-like birds—the Apteryx. (Fig. 5.) 
In the Dinosaur the ilium (Fig. 5 Dn., il.) projects forward 
as well as backwards, thus offering greater surface for attach¬ 
ment to the vertebral column. Here, then, is a bird-like 
feature added to the typical reptilian structure. Then the 
ischium is directed very far backwards and is very long; it 
lies nearer to the ilium than does the ischium in the 
crocodile, and in this respect, therefore, resembles the bird 
