LOPHIODON, Cuv.—In the year 1800 Cuvier* first announced the discovery of the fossil remains of a quadruped • Bulletin des Sciences, Paris, Nivose, an. viii., No. 34.
allied to and of the size of the tapir, in the lacustrine deposits of the Montague Noir, near Issel, department of Aude in Languedoc. The outer incisor of the lower jaw was shortened to give room to the longer corresponding incisor above, as in the tapir ; the canines offered the same proportional develop ment; but the three first molars (premolars) of the lower jaw presented a more simple structure, having the crown com pressed, and forming two cones, the front one being the largest; —in short, a structure, the type of which is presented only by the first of the three premolars (p 2.) in the genus Tapirus.* Years elapsed ere Cuvier obtained clear evidence of the structure of the upper molars of this new fossil Mammal. Such detached teeth as had been obtained from the fresh water formations near Issel were referred, owing to the way in which they departed from the type of the upper molar teeth of the Tapir, to the genus Rhinoceros. This fact is
indicative of the annectant affinities of the Lophiodon in the perissodactyle series.t Besides the character of form, the upper molar series of Lophiodon differs, like the lower one, from that in Tapirus, in the greater simplicity of the last two premolars ; these teeth have a single cone on the inner side in Lophiodon ; they have there two cones in Tapirus, forming the inner terminations of two transverse ridges, as in the true molars. These teeth in the Lophiodon differ from those in the Tapirus in the greater fore-and-aft expanse of the outer terminations of the transverse ridges, and the less depth of the cleft between them : a more complete coalescence of those parts causes a more entire outer wall of the crown, and com pletes the transition to the Rhinoceros type, towards which the Pala otherium offers the next step.