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A MANUAL OF DENTAL ANATOMY. 



processes ; and at their terminations near to the surface of 

 the tooth, the thin laminae of pulp (so thin that the radi- 

 ating pulp chambers are mere fissures) become dilated ; so 

 that on section circular canals are seen at these points, as 

 is also the case at the points where subsidiary processes 

 branch off. 



The wavy course pursued by the radiating plates of den- 



tine, and the disposition of the tubes round the dilated 

 portions of pulp chamber, render the general aspect of the 

 dentine structure very complicated ; the several "systems" ( 2 ) 



( 1 ) From tooth of Labyrinthodon, showing the nature of the connection 

 between the contiguous dentinal systems. (After a drawing of my father's. ) 



( 2 ) The term " dentinal system " is applied to the portion of dentine in 

 which all the tubes radiate from a single section of pulp chamber ; thus 

 the tooth of Labyrinthodon is made up of many dentinal systems ; the 

 same thing may be said of the tooth of Mylio bates. 



