410 Mr. Broderip on a fossil Jaw froin Stonesjield. 



carefully scraped away, and there appear, in addition, a canine 

 tooth and three incisors. There is room also for a fourth : the end 

 of the jaw is fractured, and there are traces of what nriay be the 

 alveolus of a fourth incisor. AVith this addition, the specimen 

 would give the exact number of teeth in the half of a lower jaw 

 of a Didelphis, viz. four incisors, one canine, seven grinders. The 

 fossil, which is in high preservation, is imbedded in a slab of 

 Stonesfield slate, together with Trigonue and other marine exuviae; 

 the whole mass exhibiting the oolitic structure in the most satis- 

 factory manner. 



My specimen consists of the right half of a lower jaw, the inside 

 of which is presented to view, [PI. XL] To say nothing of the 

 difference of form in the jaw-bone, M. Prevost's figure gives us the 

 representation of a portion of a lower jaw with ten grinders therein: 

 my fossil has only seven, and appears to have been part of an animal 

 generically different. The teeth are distinctly separated, and those 

 who are best qualified to judge are of opinion that the jaw did not 

 belong to a young individual. The well defined ridges and de- 

 cided features of the bone denote a full grown animal : the sharp- 

 ness of the teeth makes it probable that it was not an aged one. 



We have now the figures and descriptions of two specimens of 

 mammiferous animals which have been found at Stonesfield ; they 

 are apparently referable to two genera ; and, notwithstanding the 

 opinion expressed by M. Prevost, I will venture to add that they 

 have been found in the true oolitic series lying far beneath the 

 chalk. 



But, it appears, that there is yet another specimen. M. Prevost 

 in his memoir* says, " A ma connaissance, il a ete trouve deja a. 

 Stonesfield, ^ro/* echantillons de machoire inferieure qui paraissent 

 provenir (Vanimaux de la rncme espece; I'un est dans le musee de 

 I'universite d'Oxford, I'autre est possede par une personne qui 

 reside a Londres, et le troisieme a ete rapporle par M. Brochant 

 du dernier voyage qu'il a fait en Angleterre : ce dernier echan- 

 tillon est bien moins parfait que celui d'Oxford, dont je doime ici 

 le dessein de grandeur naturcUe, pi. 18., fig. Ij et un autre dessein 

 quadruple, pi. 18, fig. 2." 



• P. 47, of llie extract. 



