On the Upper Jaw of Megalosaurus

Publisher Website
Google Scholar
Abstract
As all who have paid attention to the Dinosauria are aware, our knowledge of the structure of the skull in these extinct reptiles is very defective. This is particularly true of Megalosaurus , of which, up to the present time, only a portion of the lower jaw has been known. I am therefore very glad to be enabled, by the kindness of Mr. Abbay, the possessor of the magnificent left upper jaw of Megalosaurus now exhibited, to make a definite addition to our means of reconstructing that monstrous Saurian. The jaw (Plate XII.) is 17·75 inches in length. At its anterior end it measures 4·3 inches in a direction perpendicular to its length. For about an inch and a half from the anterior edge ( a ), which is entire and shows the natural face of this part of the bone, the upper, or nasal, margin is nearly parallel with the lower, or alveolar, margin; but further back the bone was evidently produced into a great ascending process ( b ), which divided the nasal from the orbital region. The base of this process is fully four and a half inches long. Its anterior margin slopes rapidly backwards and upwards, and seems to have been nearly straight; while the posterior margin is concave backwards and presents a natural edge, which formed the front boundary of the orbit. The distance in a vertical line from the alveolar margin to the broken upper extremity Of the ascending process is 6·75 inches. Behind the ascending process, the vertical

This publication has 0 references indexed in Scilit: