Along that same shore, also, enormous struthious birds moved in flocks, making strides from three to five feet long, with feet eighteen inches long, lifting their heads, it may be, from twelve to eighteen feet above the ground, surpassing, as it appears, even the gigantic dinornis of New Zealand, now that the feet of the latter have been discovered. I refer to the _Brontozoum giganteum_, whose tracks are so common on the new red sandstone of the Connecticut valley. What dwarfs are we in comparison, who now consider ourselves lords of that valley! Still more remarkable for peculiarities of structure was the tribe of saurians, which were once so numerous in the northern parts of Europe and America. The ichthyosaurus, a carnivorous marine reptile, sometimes thirty feet long, had the snout of a porpoise, the teeth of a crocodile, the head of a lizard, the vertebrae of a fish, the sternum of an ornithorhynchus, and the paddles of a whale. Those paddles, corresponding to the fins of a fish, or the web feet of water birds, were composed, each of them, of more than one hundred bones. In short, we find in this animal a combination of mechanical contrivances, which are now found among three distinct classes of the animal kingdom. Its eye, also, having an orbital cavity, in one species, of fourteen inches in its longest diameter, was proportionally larger than that of any living animal. The plesiosaurus had the general structure of the ichthyosaurus; but its neck was nearly as long as its whole body--longer, in proportion to its size, than even that of the swan. The iguanodon was an herbivorous terrestrial reptile that formerly inhabited England. It approaches nearest in structure to the iguana, a reptile four or five feet long, inhabiting the marine parts of this continent. Yet the iguanodon was thirty feet long, with a thigh six feet, and a body fourteen feet in circumference. What an alarm would it now produce, to have such a monster start into life in the forests of England, where no analogous animal could be found more than half a foot in length! Surely this must have been one of the fabulous monsters of antiquity. Still more heteroclitic and unlike existing nature was the pterodactyle, a small lizard, contemporary with the ichthyosaurus and plesiosaurus. At one time anatomists regarded it as a bird, at another as a bat, and finally as a reptile, having the head and neck of a bird, the body and tail of a quadruped, the wings of a bat, and the teeth of a saurian reptile. With its wings it could fly or swim; it could walk on two feet or four; with its claws it could climb or creep. "Thus," says Dr. Buckland, "like Milton's fiend, all qualified for all services, and all elements, the pterodactyle was a fit companion for the kindred reptiles that swarmed in the seas, or crawled on the shores of a turbulent planet."