AMPH1THERIUM. 33 



" 2nd. Neither can they be referred to an insectivorous 

 Monodelph allied to the Tupaia or Centetes. 



" 3rd. If we deem ourselves justified in regarding them 

 as of the class Mammalia, the molar portion of their dental 

 system brings them nearer to the family of the Seals than 

 to any other. 



" 4th. But it is infinitely more probable, from analogy 

 with what we know of the Basilosaurus found in America, 

 in a formation likewise secondary, that they ought to be 

 referred to a genus of the sub-order of Saurians. 



" 5th. That in any case they must be distinguished by a 

 diiferent generic name, for which purpose we propose that 

 of Amphithermm, as indicating their ambiguous nature. 



" Lastly ; the existence of the remains of Mammalia 

 anterior to the formation of tertiary strata is not at all 

 proved by the Stonesfield fossils on which we have now 

 treated, although we are far from asserting that Mammalia 

 were not in existence during the secondary period." 



Dr. Buckland, shortly after the publication of M. de 

 Blainville's doubts, visited Paris, taking with him the 

 original specimen seen by Cuvier, and a second specimen, 

 also from Stonesfield, more perfect as regards the jaw-bone, 

 but less perfect in reference to the teeth : and he submitted 

 both these specimens, in the absence of M. de Blainville, to 

 M. M. Valenciennes and Laurillard. The results of their 

 comparisons were communicated by M. Valenciennes to the 

 Academy of Sciences,* in September 1838. The second 

 specimen was referred to the species (Didelphys Bucklandi 

 Brod.) which had been described and figured by my friend 

 Mr. Broderip in the Zoological Journal ;^ but in this latter 

 determination I cannot agree with M. Valenciennes, who has, 



* Comptes rendus de TAcad. des Sciences, Sept., 1838, p. 572. 

 t Vol. iii. p. 408, pi. xi. 



1\a \ 



