34 AMPHITHERIID ©. 
indeed, himself afforded sufficient grounds for such dissent 
by stating, that ‘he had convinced himself that the second 
jaw must have had ten molar teeth, as in the first speci- 
men;” the Did. Bucklandi having had only seven, or at 
most eight, molars. 
In regard to the question of the general affinities of these 
fossils, M. Valenciennes arrived at the conclusion that the 
jaw, described and figured by M. Prevost and Dr. Buck- 
land, not only belonged to a mammalian but likewise to a 
marsupial animal, and accordingly proposed for it a third 
generic name, indicative of these presumed affinities, viz., 
Thylacothervwi. 
The arguments of M. Valenciennes were opposed, in a 
second detailed memoir by M. de Blainville,* who con- 
cluded by stating, “that he felt himself compelled to pause, 
at least until fresh evidence was produced, in the conviction 
that the portions of the fossil jaws found at Stonesfield, 
probably not to a 
certainly did not belong to a marsupial 
mammalian genus, either insectivorous or amphibious— 
that, on the contrary, it was most likely the animal had 
been oviparous, and, in regard to the opinion, founded on 
the analogy of the Basilosaurus, a large fossil reptile of 
America, the teeth of which display the peculiarity of pos- 
sessing a double root, that it might have been an animal of 
the Saurian order :” —and ‘that had not M. Agassiz de- 
cidedly given his opinion against the fossils in question 
belonging to fishes, he would rather have been led to sup- 
pose that they might have been the remains of an animal of 
that class.” 
‘“‘ In conclusion,” adds M. de Blainville with naiveté, ‘I 
ought also to announce to the Academy, that the scientific 
* “Nouveaux Doutes sur le prétendu Didelphe de Stonesfield ; Comptes 
rendus,” October 6th, 1838, p. 727. 
