FOSSIL REPTILES. 3^3 



the wide part, proceed to unite in this point, are strongly ser- 

 rated. The external and enamelled face of the tooth has two 

 longitudinal ridges, very obtuse and not projecting, which 

 divide it into three parts also longitudinal and very slightly 

 concave. 



In the business of mastication, this tooth at first is worn in 

 the point, and gradually all the part whose edges are denticu- 

 lated disappears by detrition. A truncation at the same time 

 is produced on the tooth, which grows broader and broader, 

 but which is always oblique, because the external and ena- 

 melled face is less worn than the rest. It is only when all the 

 denticulated part is removed that one might be tempted to take 

 these teeth for those of herbivorous mammalia, worn as far as 

 the root, for there are no lineaments of enamel on the crown, 

 and even the want of them would oblige us to suppose these 

 teeth to be incisors, were we to attribute them to mammalia. 

 But this would be a supposition exceedingly difficult to admit, 

 for there are no incisors of mammalia which in the slightest 

 degree resemble the teeth in question. 



Some of these teeth are smaller than the others, and the 

 smallest have usually on their external face but one obtuse 

 longitudinal ridge, but on the sides many smaller and sharper 

 ridges are observable which form striae there. Some are also 

 found with a simple trenchant edge, without denticulations, 

 slightly convex at their two faces, and terminated by an obtuse 

 point, and which tolerably resemble the canines or lateral incisors 

 of tapirs, or other animals with short canines. These differ- 

 ences are probably attributable to the different positions of the 

 teeth in the mouth of the animal. These teeth do not afford 

 the only indications of the existence of gigantic species of 

 saurians, equal, or nearly so, to the megalosaurus, the animal 

 of Maestricht, and the crocodiles, in those remote ages. 



Among the bones collected at Honfleur, in the possession of 

 M. Cuvier, are vertebrae of several sorts, which he could not 

 refer to any of the species hitherto described, and which may 



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