Hadrosaurus , a gigantic extinct dinosaurian reptile, living on the shores and in the forests of the cretaceous epoch, abundant in the region of New Jersey, where its remains have been found. It attained a length of 30 ft., its femur having been found 5 ft. long, considerably longer than that of the great iguanodon of England; the fore limbs were less than half the size of the hind, hut the tail was of immense strength. It was evidently a land animal, and its grinding teeth indicate the vegetable character of its food. Its favorite attitude must have been to support itself upon the very-strong hind limbs and tail, after the manner of the megatherioids, reaching to the foliage on which it fed by its smaller and freely movable anterior limbs. As the iguanodon seems to have been the prophetic type of the great pachyderms of the tertiary age, the hadrosau-rus seems to point to the coming of the huge edentates like megatherium and mylodon. A fine restoration of this animal (hadrosaurus Foulki, Leidy) is in the museum of the academy of natural sciences at Philadelphia.