897 



The following, to No. 5876 inclusive, illustrate the dental system, its changes and deve- 

 lopment, in Man : 



5833. A section of the Human skull, including the upper and lower jaws, from the 

 right side of which the teeth have been extracted, and are displayed separately. 



Their nature is indicated by their symbols : i 1, i 2, the incisors ; c, the canine ; p 3, 

 p 4, the bicuspids, answering to the third and fourth premolars of the typical series ; m 1 , 

 m 2, m 3, the first, second and third molars. The prominence of the nasal bones, verticality 

 of the alveolar part of the upper jaw, and moderate size of the molar teeth, indicate this spe- 

 cimen to be from a European, and probably an Englishman. In one premolar of the upper 

 jaw the two fangs are distinct ; in the other premolars they are connate. The first molar of 

 the upper jaw has three diverging fangs, that answering to the outer fang of the premolar 

 being bifid : in the second and third upper molars the divisions of the corresponding fang 

 are connate : the lower molars are implanted by two fangs each. Compare this insertion of the 

 molar teeth with the more complex insertion of the molars in the Australian skull (No. 5316). 

 The present, or a similar preparation, is figured in Hunter's Work ' On the Teeth,' pi. iii. 

 figs. 1 & 2. 



Hunterian. 



5834. A section of the Human skull, including the left halves of the upper and lower 

 jaws, from which the outer walls of the alveoli have been removed. 



The first molar above is implanted by three roots, the second molar above and the first 

 below by two roots, one external to the other in the former, one behind the other in the 

 latter : in the other molars the fangs are connate. A small osseous excrescence projects from 

 the inner alveolar wall of the third molar of the upper jaw. 



Mus. Brookes. 



5835. The upper and lower jaws of a Child' which has acquired the deciduous series 

 of teeth and the first molars of the permanent series. The roots of the teeth 

 in place and the crowns of the successional teeth are exposed by the removal 

 of the outer alveolar walls. 



The nature of the teeth exposed is indicated by their symbols : d i, d i, the deciduous 

 incisors ; d c, the deciduous canine ; d 3, d 4, the deciduous molars, answering to the third 

 and fourth in the typical series ; these illustrate the deciduous formula in Man, viz. 

 i ^, c j^J, m ?=|=20. The permanent teeth in course of calcification are : 1, i 2 ; e ; 

 p3, p4; m.2: m 1 is in place and requires only the completion of the fangs ; the matrix of 

 m 3 has not begun to be calcified. The outer part of the root of m 1 bifurcates and diverges 

 like the corresponding roots of d 4 and d 3, and, save in size, it more closely resembles d 4 

 than m 1. 



This elegant preparation was made for JOHN HUNTER by his Pupil WILLIAM LYNN, 

 afterwards President of the Royal College of Surgeons. 



Hunterian. 



5 T 



