Cuvier thought that it might have been seventy feet in length.

It was carnivorous, and therefore more ferocious than the iguanodon, and more ready to attack.

Its head was like that of a crocodile, its body massive like that of an elephant, yet larger; its tail was small, and it stood high on its legs, so that it could run with great speed.

It was not covered with bony armor, but had probably a hide thick enough to serve the purpose of shell or bone.

Its teeth were constructed so as to cut with their edges, and the movement of the jaws produced the combined effect of knife and saw, while their inward curve rendered impossible the escape of prey that had once been caught.