364 PALEONTOLOGY. 



character of the molar tooth of Stcreognathus (fig. 125, e). 

 The oblique ridge from the outer and hinder lobe (c) abuts 

 against the intermediate tubercle (e). The nearest approach to 

 the above dentition is made by the extinct 

 _j Hyracotherium ; * also a fossil from the Lon- 

 don clay. 



The third trochanter on the femur of 

 d Pliolophus, and the association of three meta- 

 tarsals in one portion of the matrix, as if be- 

 True molar, lower losing to the same hind foot, confirm the 



jaw (magn.), Ste- & ° ' 



reognathus ooli- perissodactyle affinities of that genus as 

 shewn by the skull. 

 Pliolophus and Hyracotherium form a well-marked section 

 of the odd-hoofed herbivores which preceded the palseotherian 

 family in time, and retained more of the general ungulate 

 type. This is shewn by the graduation of the tapiroid 

 modification of the molar teeth into one more nearly resem- 

 bling that of the Anthracotheria and Chceropotami, by the 

 absence of the postero-internal cone on the ultimate premolar, 

 by which all the premolars are, as in artiodactyles, less com- 

 plex than the true molars, by the form and position of the 

 nasal bones and by the structure of the external nostril. 



Genus Lophiodon, Cuv. — In the year 1800 Cuvierf first 

 announced the discovery of the fossil remains of a quadruped 

 allied to and of the size of the tapir, in the lacustrine deposits 

 of the Montagne 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 premolars of the lower jaw presented a 

 more simple structure, having the crown compressed, and 

 forming two cones, the front one being the largest ; — in short, 



* Hist. Brit. Foss. Mamm, p. 419, figs. 165, 166. 

 f Bulletin cles Sciences, Paris, Nivose, an. viii., No. 34. 



