94 MICROSCOPIC ANATOMY OF THE TEETH 



of the beak-like jaws. Large tubes resembling those of 

 a true vascular dentine are seen in the dentine and in several 

 places even entering the enamel. They not only form loops 

 at the amelo-dentinal junction which encroach upon the 

 enamel, but broad tubes pass in several places well into its 

 substance. These are not merely the small isolated loops 

 described by C. S. Tomes in Sargus, but they form a connected 

 system (fig. 48). 1 



d 



FIG. 48. Vascular loops in tooth of Pseudoscarus. e. Enamel ; 

 d. dentine Ground section. (x!50.) 



In the maxillary teeth of Scarus, according to Von Boas 

 (4), the dentine is much more reduced than in the pharyn- 

 geal teeth, and he considers that a resorption of the dentine 

 occurs after its first formation and describes absorption 

 contours or Howship's lacunae between the enamel and 

 dentine. 



In a freshly preserved specimen of Pseudoscarus, kindly 

 sent to the author by the Curator of the New York Aquarium, 

 he found confirmation of these observations of -Von Boas, 

 as shown in fig. 49, photographed from preparations from 

 this specimen. In many places absorption lacunae are seen 

 between the enamel and the dentine in the superimposed 

 teeth of the maxilla. These can also be seen in the pharyn- 



1 A similar condition in the crown of the incisor teeth of Sargus ovis is 

 described on p. 258. 



