Dinosaurs, with Special Reference to the American Museum Collections

DINOSAURS (

nosaurs-Stegosaur

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rom the bird-footed biped Iguanodonts they are evidently related to them, for the teeth are similar, and the horny beak, the construction of the pelvis, the three-toed hind foot and four-toed front foot all betray relationship. From what we know of them it seems probable that they evolved from Iguanodont ancestors, developing the bony armor as a protecti

OSAU

long and five or six inches thick at the base. In the neck region and probably elsewhere the skin had numerous small bony nodules and some larger ones imbedded in its substance or protecting its surface. The head was absurdly small for so huge an animal, and the stiff thick tail projected backward but was not long enough to reach the ground. The hind limbs are very long and straight, the fore limbs relatively short, an

tons which he described are mounted in the Yale and National Museums. Another skeleton was found in the famous Bone-Cabin Quarry, near Medicine Bow, Wyoming, by the Americ

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osaur Ankylosaurus, from Upper Cretacic (Ed

LOSA

osaur's body was narrow and compressed, in this animal it is exceptionally broad and the wide spreading ribs are co?ssified with the vertebrae, making a very solid support for the transverse rows of armor plates. The head is broad triangular, flat topped and solidly armored, the plates consolidated with the surface of the skull and overhanging sides and front, the nostrils and eyes overhung by plates and bosses of bone; and the tail e

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urus, top view of

gave any adequate notion of its character or gigantic size. From a partial skeleton discovered in the Hell Creek beds of Montana, and others in the Edmonton and Belly River formations of the Red Deer River, Alberta, it has been poss

the Jurassic, Comanchic and Cretacic formations of Europe. The best known are Scelidosaurus of the Lower Jurassic of England