. A history of British fossil mammals, and birds . ander s possession, crag adhered to it in considerablequantity, and he has no doubt that it had been washedfrom Easton, about a mile and a half north of weight of the tooth is two pounds, five ounces anda half; its length is about six inches, and its breadth threeinches and a half; and, although it had been washed eightmiles, only three of the crowns had been injured. From an inspection of the cast, it appears that thefirst and fifth pairs of tubercles, and the posterior tuber-eulatc talon, have suffered fracture. The effects of
. A history of British fossil mammals, and birds . ander s possession, crag adhered to it in considerablequantity, and he has no doubt that it had been washedfrom Easton, about a mile and a half north of weight of the tooth is two pounds, five ounces anda half; its length is about six inches, and its breadth threeinches and a half; and, although it had been washed eightmiles, only three of the crowns had been injured. From an inspection of the cast, it appears that thefirst and fifth pairs of tubercles, and the posterior tuber-eulatc talon, have suffered fracture. The effects of abrasionfrom the acts of mastication have extended to the fourth 280 PKOBOSCIDIA. pair of mastoid eminences : besides the injury to the crownfrom accidental violence, all the fangs of the tooth havebeen broken away. The molar tooth (%. 98) of the Mastodon angustidens,which was obtained by Mr. Robert Fitch, of Nor-wich, from the fluvio-marine crag at Thorpe, near that city,strikingly demonstrates the generic differential characters Fiy. Penultimate upper Molar, Mastodon aiigustidens, Fluvio-marine Crag, Thorpe,Norfolk. 4 nat. size. between the molars of the Mastodon and those of the Mam-moth. The coat of enamel (e), which invests the dentinaleminences {d) of the crown, is three times as thick as thatin the Mammoths molar of thrice the size, which is figuredat p. 231 (fig. 90) ; and it is almost twice as thick as theenamel of the molar tooth (fig. 88) of the African Ele-phant,—the existing species which makes the nearest ap-proach to the Mastodon in the structure of its teeth andin its general proportions. The cement of the Masto-dons tooth, on the other hand, forms so thin a layer,that it can only be detected by the naked eye at thebottom of the clefts between the mastoid eminences. Theseare arranged subalternately in four pairs, and a tuberculateeminence terminates the base of the crown. This numberof the chief divisions of the grinding surface, together with MAST
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Keywords: ., bookaut, bookcentury1800, bookdecade1840, booksubjectpaleontology
