XXII 



ON THE DEVELOPMENT OF THE TEETH, AND ON THE 

 NATURE AND IMPORT OF NASMYTH'S "PERSISTENT 



CAPSULE" 



Quarterly Journal of Microscopical Science, i. 1853 



I AM desirous of setting forth in the course of the following pages, 

 as concisely as may be, the principal results to which I have been 

 lately led in the course of working over the development of the 

 human and of some other teeth. I have directed my investigations, 

 not to the general phenomena of dentition, our knowledge of the 

 course of which, firmly established many years ago by Professor 

 Goodsir, has not been affected, so far as I am aware, by any subse- 

 quent investigations, but to those points of structure and development 

 upon which every writer, from the time of John Hunter to the present, 

 seems to have formed, with more or less plausibility, an opinion of his 

 own, different from that of all others. 



I must suppose such a knowledge of the general course of develop- 

 ment of the teeth as may be found in the ordinary hand-books of 

 physiology — my limits allowing no unnecessary disquisition — and 

 proceed at once to the questions whose discussion I am about to 

 attempt. These are, firstly : What are the three structures which are 

 concerned in the development of the teeth, viz., the pulp, the capsule, 

 and the enamel organ, morphologically, or in relation to the parts of the 

 mucous membrane from which they are developed ? 



Secondly : What is the relation of the dentine, the enamel, and the 

 cement, to these organs ? 



Thirdly : What is the relation of the histological elements which 

 enter into the composition of the soft parts, to the dentine, enamel, 

 and cement, which are formed from, or within them. 



These questions, I think,'involve all the essential points connected 



