4 OBSERVATIONS UPON 



M. de Blainville concludes his task by an invitation for 

 fresh observations, which may furnish new elements to the 

 argument, for or against the opinion hitherto admitted. 



The memoir of M. de Blainville proves, that if he had had 

 the advantage of examining the fragments themselves, he 

 would have left no doubt upon the subject. 



Having myself been more fortunate, I hastened in some 

 sort, to reply to the appeal which he made, in the name of 

 the Academy, and it is this which has determined me to re- 

 quest to-day, permission to read the memoir which I now 

 submit to your approval. 



Dr. Bucldand has just brought over, among other very va- 

 luable geological specimens, the two jaws found in the schist 

 at Stonesfield, and preserved in the Oxford Museum. He 

 very willingly entrusted them to me during his stay at Paris, 

 and allowed me to have models of them taken, which I have 

 presented to the Academy. I have compared the originals 

 with the different mammals and reptiles in the cabinet of the 

 Jardin des Plantes, and I believe that I have arrived, by this 

 comparison, at a confirmation of the justice of Cuvier's opi- 

 nion. 



One of the two jaws submitted to my examination is the 

 very one which Cuvier for a short time inspected ; the Didel- 

 phis Prevostii. The other, subsequently discovered, is of the 

 same species as that described and figured by Mr. Broderip, 

 his Didelphis Bucklandii. 



Another jaw, which I believe to be of this latter species, 

 makes a part of Mr. Sykes's collection. It is this specimen 

 which Messrs. Phillips and Lyell allude to when speaking of 

 the fossils in their works. 



This specimen, which I am able to refer to, from the draw- 

 ing sent by Mr. Phillips to M. Cuvier, and which M. Lau- 

 rillard has had the goodness to lend me, is less complete than 

 the two others, for the angle is wanting, as well as the con- 

 dyle, and the largest part of the ascending ramus ; the latter 

 however has left its impression upon the stone, which serves 

 as a matrix. 



This proves that we now have four of these jaws belonging 

 to two distinct species of vertebrated animals ; and so far I 

 perfectly agree with M. Agassiz, who appears to have seen a 

 fifth, and who remarks, it is singular that we have never yet 

 discovered any bone belonging to any other part of the ske- 

 leton. 



The jaw first known has been so fully described by M. C. 

 Prevost, in his memoir upon the Stonesfield fossils, that it 

 will be needless to recapitulate here any details of its general 

 form. 



