IX. On the structure and development of the teeth of ophidia

Abstract

It has been usual to regard the dentine as the most, and the enamel as the least constant of the dental tissues, the cementum in this respect occupying an intermediate position —this relation being held to have been established as a matter of observation, no less than as a legitimate inference from the process of development. It has, however, been shown by Kölliker and Waldeyer in the case of mammals, and by Santi Sirena and myself in the case of Batrachia and Sauria (the present paper extending these observations to the Ophidia) that the enamel-organ is absolutely the first structure which can be recognized in the vicinity of a future tooth, and that the dentine-organ or “ papilla ” can only be recognized at a later stage. This very early appearance of an enamel-organ would seem to point towards the enamel being both more important and more widely distributed than would be indicated by the statement that “ the enamel is the least constant of the dental tissues ”. I was not therefore much surprised to find that the teeth of all the Ophidia which I have examined, amounting to some ten genera, are coated with a thin layer of enamel .