536 BAL^ENODON. 



GET ACE A. DALMNODON. 



Fiy. 226. 



Portion of fossil tooth of Balaenodon, Red-Crag, Felixstow. Nat. size. 



BAL^NODON PHYSALOIDES. Cachalot-like 

 Balaenodon.* 



THE fossil above figured was submitted to me by Mr. 

 Bowerbank, in the year 1840, with a request that I would 

 endeavour to ascertain its real nature; and having ob- 

 tained the permission of its owner, Mr. Brown of Stan- 

 way, to take a section from it for microscopical ex- 

 amination, I found by this insight into its intimate struc- 

 ture, that it was a fossil tooth, belonging to a Mammalian 

 animal ; and in that class, bearing the nearest resemblance 

 in the thickness and structure of the outer layer of cement 

 immediately surrounding the dentine, to the teeth of the 

 Cachalot (Physeter tnacrocepJialus). 



The most obvious distinction was, that, great as is the 

 thickness of the outer coat of cement in the Cachalot, 

 (fig. 218, c,) it was still greater in the fossil, (fig. 219, c,) 



* Ziphius, generic name of a fossil Cetacean, and tiovs, a tooth. 



