THE ATTACHMENT OF TEETH 



359 



dentine is not calcified, but appears to be somewhat of the con- 

 sistence of whalebone, although as a mesoblastic product 

 having no other analogy with it ; acids have no effect upon it. 

 It contains no vascular canals, and at its upper portion at/ in 

 this figure is continuous with the dentine at the inner margin 

 of the pulp cavity, and in this portion a few scattered vascular 

 canals are seen, but it terminates at e, where the fibres of 

 the fibrous band d are inserted into it. These fibres again 



FIG. 238. Section of decalcified tooth of Hake (Merluccius) taken to one 

 side of middle line, showing anterior hinge on one side (a.) stained with 

 Mann's methyl eosin. e. Triangular space ; d. insertion of calcified tooth 

 into fibrous portion of posterior hinge ; s. stiffened elastic part of posterior 

 hinge ; i. junction of fibrous part with s. ; b. bone of attachment ; k. in- 

 sertion of posterior hinge into bone. ( x 50. ) 



unite at i with the outer band s. Between these two 

 portions of the hinge is an elongated space in which separated 

 strands of fibres are seen. That the two portions of the 

 hinge above described are of a different structure is shown 

 by their staining reactions. When sections are stained with 

 methyl eosin, the dentine and bone are stained red, but the 

 fibrous band/ in the plate is of a bright blue, taking the colour 

 in the same manner as uncalcified connective tissue ; the 

 posterior portion of the band s is coloured uniformly red. 



