Mr. Broderip on a fossil Jaw from Stonesfield. 409 



other animals that are found at Stonesfield are not less extraordi- 

 nary than tlie Megalosauius itself. Among the most remarkable 

 are two portions of the jaw of the Didelphys or Opossum, being 

 of the size of a small Kangaroo Rat ; and belonging io a family 

 which now exists chiefly in America, Southern Asia, and New 

 Holland. I refer the fossil in question to this family on the au- 

 thority of M. Cuvier, who has examined it ; and, without the 

 highest sanction, I should have hesitated to announce such a fact, 

 as it forms a case hitherto unique in the discoveries of geology ; 

 viz. that of the remains of a land quadruped being found in a 

 formation subjacent to chalk." 



The learned author of the article " on the Transactions of the 

 Geological Society of London," in the 34th vol. of the Quarterly 

 Review, after referring to this passage, says, * " As this fact is 

 completely at variance with all preceding observations, it is not 

 surprising that it has been received with some scepticism. M. 

 Constant Prevost, who has himself visited Stonesfield, has lately 

 published a memoir, in which every argument that can be urged 

 to invalidate Dr. Buckland's opinion is put forth with great ability 

 and with a spirit of fairness; but all this has not in the least 

 shaken our reliance on the accuracy of the statement. In the first 

 place it is admitted that the remains in question were decidedly 

 imbedded in the Stonesfield slate. To this stratum *' in working 

 the quarries at Stonesfield, they descend by vertical shafts through 

 a solid rock of cornbrash and stratified clay, more than 40 feet 

 thick."+ M. Cuvier, who has re-examined the fossil in questiou 

 since the objection was started, still pro\»ounces the animal to 

 have been mammiferous, resembling an Opossum, although of an 

 extinct genus, and differing from all known carnivorous mammalia 

 in having ten teeth in a series in the lower jaw. 



The ten teeth represented in (he figure accompanying M. 

 Prevost's memoir,| are evidently giinders, and somewhat resem- 

 ble the molar teeth of my specimen, which has, however, only 

 seven grinders; and, when it was lent to Dr. Buckland, they were 

 the only teeth apparent. He, however, caused the stone to be 



• P. 529. 



+ Trans. Geol. Soc. vol. i. p. 393. Second Series. 



X PI. 18. fij;. 1,2. 



