Fig. 37.—Skull of Mosasaurus Hoffmanni.
The original is 41/2 ft. by 21/2 ft.
Fig. 38.—Teeth of Mosasaurus (half natural size).
1a, 2a, transverse sections of the teeth.
The entire backbone of the Maestricht animal appears to have consisted of one hundred and thirty-one vertebræ, of which ninety-seven belonged to the tail. The total length of the skeleton is estimated at twenty-four feet, and the head was about one-sixth of the total length. The tail is only ten feet long, whereas in a crocodile the tail exceeds the length of the body. Although in his day the limbs of the Mosasaurus were imperfectly known, Cuvier rightly considered them to be adapted for swimming, and, with his usual foresight, concluded that this monster was a marine reptile of great strength and activity, having a large tail flattened vertically and capable of being moved from side to side with such force and rapidity as to be a powerful organ of propulsion, capable of stemming the most agitated waters. The large conical recurved teeth, the largest of which was nearly three inches long, are well seen in Figs. [37] and [38]. Dr. Mantell was fortunate enough to find, in the year 1820, some vertebræ from the English Chalk near Lewes, which were identified as belonging to a Mosasaurus.
In 1831 a portion of a lower jaw with large conical teeth was discovered in the Chalk near Norwich. But these teeth were not quite similar to those of the Maestricht specimen, and Professor Owen therefore founded upon them the new genus Leiodon.[35] But Leiodon must have been very similar to Mosasaurus.
[35] Greek—leios, smooth, and odous, tooth.