60 AMPHITHERIIDjE. 



dyloid (a) and coronoid (5) processes have both left their 

 impressions on the matrix : the angle of the jaw is frac- 

 tured: there is the same shallow, wide and smooth groove (e) 

 near the lower margin of the jaw, and the same notch (/) 

 in the symphysis, as in the Amphitherium Prevostii, and 

 the Myrmecobius. The chief value of the specimen in the 

 Museum at York, arises out of the very perfect state of the 

 crowns of the molar teeth, the peculiar form of which, 

 giving one of the characters of the extinct genus, could not 

 be satisfactorily determined from the specimens before 

 described. That the fossil in question belongs to the genus 

 Amphitherium is proved by the number and nature of the 

 teeth which it contained ; but its difference of size, as com- 

 pared with the jaw of Amphitherium Prevostii, is greater 

 than has been observed in mature individuals of the same 

 species of Placental or Marsupial Insectivores. I have, 

 therefore, indicated the species which the present fossil 

 represents by the name of Amphitherium Broderipii, in 

 honour of the Naturalist and Geologist, to whom we are 

 indebted for the first accurate description and figure of a 

 Stonesfield Mammalian fossil.* 



For the opportunity of describing and figuring the half- 

 jaw of the Amphitherium Broderipii, in the Geological 

 Transactions, I was indebted to Professor Phillips, to whom 

 I again beg to record my obligations for the facilities 

 afforded me in studying this additional evidence of the 

 oldest Mammalian inhabitants of this Planet. 



* See the " Observations on the Jaw of a Fossil Mammiferous Animal, found 

 in the Stonesfield Slate. By W. J. Broderip, Esq., Sec. G.S. F.L.S., &c." 

 Zoological Journal, 1 828, voL iii. p. 408, pi. xL 



