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Moscesaurus. The saurus of the Meuse, the Maestricht 



animal of Cuvier. 



As Cuvier has not yet given it a name, this name is 

 suggested by Mr. Conybeare until he has done so. 



Species I. Described by Cuvier. 



II. Lacerta gigantea of Soemering. 



This animal is considered, by Cuvier, Soemering, and 

 A. Camper, as sui generis ; its head placing it irrevocably 

 between the monitors and the iguanas. But, as is observed 

 by Cuvier, how enormous is its size compared with all known 

 iguanas and monitors. None of these have a head longer 

 than five inches ; and that of this fossil animal approaches 

 to four feet. 



Its mode of dentition distinguishes it from the croco- 

 dile. Its teeth have a central hollow, only whilst grow- 

 ing; this at length fills up, and they generally become 

 entirely solid, being fixed to the jaw by means of an osseous 

 and fibrous body, which, although they are intimately 

 united with it, is very different from the proper substance 

 of the teeth. The replacing tooth grows in its particular 

 alveolus, which is formed at the same time ; and, at length, 

 it pierces the osseous body bearing the former tooth, at its 

 side or across its substance ; and, as it grows, it detaches 

 this body by interrupting its organic connection with the 

 jaw, and occasions it to fall, like the horn of the stag, by a 

 species of necrosis, the old tooth falling with it : the new 

 tooth, with its osseous body, improperly called its bony root, 

 takes the place the old tooth has left. 



In the lower jaw are fourteen teeth, nearly regular in 

 size, and about ten or twelve foramina, or rather holes, for 

 the passage of vessels, &c. The coronoid apophysis is 

 raised, obtuse, and wide in its anterior margin, as in the 

 monitors. In these, and other points, the jaws agree more 

 with that of the monitor than with any other saurian. But 



