AMPHITHERIID.E. 



broken off close to the sockets ; both the fifth and fourth 

 false molars are entire ; the anterior cusp presents the 

 same superior size as in the first specimen. The thick 

 external enamel, and the silky, iridescent lustre of the 

 compact ivory, are beautifully shown in these teeth. The 

 third and second grinders are more fractured than in the 

 first specimen, but sufficient remains to show that they 

 possess the same form and relative size; but the most 

 interesting evidence, as regards the teeth, which the pre- 

 sent jaw affords, is the existence of the sockets of not less 

 than seven teeth, anterior to those above described. Of 

 these sockets the four anterior ones are small and simple, 

 like those of the mole, and are more equal in their size and 

 interspaces than in the Didelphys : the fifth socket con- 

 tained a small premolar with double fangs ; the next is 

 a similar socket, and then come four other premolars in 

 place with more or less perfect crowns : between the last 

 of these premolars and the last molar the empty alveoli 

 agree in number with, and occupy the same extent as, 

 the first five true molars in the jaw, cut 16. This fossil 

 afforded evidence, therefore, that the dental formula of the 

 AmpMtJierium included thirty-two teeth in the lower jaw ; 

 sixteen on each side. 



Thus the AmpJiitherium differs more considerably than 

 the evidence in Cuvier's possession showed, from the genus 

 Didelphys in the number of its teeth. Indeed at the time 

 when the great Palaeontologist wrote respecting it, believ- 

 ing it to have had ten molars, no mammiferous ferine 

 quadruped was known to possess a greater number of 

 these teeth than the Cape Mole or Chrysochlore, which 

 has nine molars on each side of the upper jaw, and eight 

 molars on each side of the lower jaw. The Chrysochlore, 

 however, is not the only species in which the molars 



