Page:Popular Science Monthly Volume 34.djvu/486

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Who were these assailants? Probably also dinosaurs belonging to the carnivorous branch of this order. One of the best known of them is the megalosaurus, an animal of about the same size and way of living as the iguanodon, marching or wading mostly on its hind-legs. A carnivorous animal is characterized

PSM V34 D486 Teeth of iguanodon.jpg
Fig. 4.—Teeth of Iguanodon.

by its teeth, which must be apt to seize and lacerate its prey. The teeth of megalosaurus were few in number, large, flattened, of the shape of a saber, and with sharp, crenulated edges. Megalosaurus was a European dinosaur. One of the best-known American carnivorous dinosaurs of the Jurassic formation has been called ceratosaurus, on account of a large horn on the skull.

PSM V34 D486 Head of megalosaurus.jpg
Fig. 5.—Head of Megalosaurus, one tenth natural size (restored by Phillips).

If the reptiles mentioned heretofore, with a length of twenty-five to thirty feet, must be called beasts of quite a respectable size, they were by no means the giants of their order. The largest known dinosaurs have been found in the Jurassic formation of the western slope of the Rocky Mountains, in Colorado and Wyoming. In the A Museum of Yale College, in New Haven, there are