458 



DR. H. W. MAEETT TIMS OK THE 



pm- 4' ) ^vitli a lahial downgrowth of the dental lamina ( pm. 4" ). 

 I would here digress to remark on the peculiarity of this down- 

 growth. It assumes at its free extremity a well-marked spherical 

 shape, the epithelial cells becoming concentrically arranged, the 

 central ones having a translucent appearance. It is distinctly 

 connected with tlie dental lamina. Mr. Woodward tells me he 

 has found a simikr structure, in precisely the same situation, in 



"'Aj'^'-r 



pra.4" 



pm. 4' 



Fig. 6.~Transverse section through the developing Upper Carnassial of the 

 7 weeks' foetal Pup. 



Oymnura. I am not able to give an explanation of the condi- 

 tion, but from the facts of its connection with the dental lamina 

 and its presence in precisely the same situation in these forms, 

 1 do not think it is a chance s-ttucture, and it is possible that it 

 may represent the remains of the predecessor to this tooth which 

 has taken on this peculiar character. The point is, however, I 

 think, worth further investigation. 



At a later period in the development of this tooth a well- 

 marked lingual downgrowth of the dental lamina is to be seen, 

 and thus the conditions of its development are identical with 

 those found in the development of the molars. 



