IRREGULARITIES OF THE DENTAL APPARATUS. 733 



than in others, but this disposition of the latter, not having any influ- 

 ence upon the qualities of the animal, becomes unimportant as to its 

 practical application. It is so irregular that it may exist in one or in 

 several incisors, on one side only, or on both at the same time ; it is so 

 frequent that it may be seen in almost all horses at some period or other 

 of their life. 



Hence we have the best reason for saying * that the levelling of the 

 incisors has much less value, from a practical point of view, than the 

 form of the central enamel, since the infundibulum is so irregularly 

 filled with cement, according to the subjects. The successive con- 

 figurations of its central enamel, as the tooth wears off, enables the 

 practised eye to determine with enough precision to what phase of wear 

 it belongs. Its absolute depth seems to us more constant in the same 

 teeth than is generally believed. On the other hand, admitting that 

 its length may become excessive, there are other characteristics drawn 

 from the form of the tooth, its direction, and its coloration, which 

 indicate more. These, in themselves, would be sufficient in nearly 

 all cases to justify an opinion, but there is another one which, by its 

 presence, should remove all doubts : it is the dental star, a yellowish, 

 narrow, transverse line, which ordinarily becomes visible, at eight years 

 of age, upon the dental table between the anterior border of the tooth 

 and the ring of central enamel surrounding the external dental cavity, 

 or its cul-de-sac, when the external cavity no longer exists. 



b. False Beguite. The persistence of the cul-de-sac of the 

 central enamel at a period when it should no longer exist constitutes 

 false beguite, and causes the horse to be designated false begu. (Plate 

 XXXIII.) This cul-de-sac, it is known, is filled with cement, and 

 appears on the table as a circular ring of enamel standing out in 

 relief. 



It appears thus first in the pincers, then in the intermediates, and, 

 finally, in the corners, as soon as their levelling has been completed. 

 If the wear is normal, and if the external cavity has the ordinary 

 depth, it should assume this disposition at eight years in all the inferior 

 incisors, and its disappearance takes place only at the age of twelve or 

 thirteen years. 



It is hardly possible to explain this tardy disappearance of the 

 central enamel or the false beguite by admitting an excessive length 

 of its external cavity, all things being equal otherwise. It may be 

 surmised, nevertheless, that this anomaly may be due also to a greater 



1 Goubaux et Barrier, Archives vt6rinaires, annee 1881, p. 133. 



