THE TEETH OF VEETEBEATES 



47 



is no elasticity in the hinge. The other form pos- 

 sesses no special elastic fibres but the hinge is 

 elastic (Figs. 9 and 10). 



3rd. By Ankylosis, when there is no interven- 



Fig. 10. — Hinged tooth of Hake (Merluccius). (After Tomes.) 



ing membrane, but the teeth and the jaw-bone are 

 ossified into one continuous piece like an anky- 

 losed joint. Such teeth are sometimes but slightly 

 attached, or, again, so strongly as to bring away 

 a piece of bone when detached. Ankylosed teeth 



