226 Proceedings of the Royal Physical Society. 
between the canine and lateral incisor is much greater than 
the intervals between any of the other teeth. The central 
incisors are also considerably larger than the lateral. They 
all present, at their cutting edges, a serrated appearance, 
evidently produced artificially by filing, the central in- 
cisors exhibiting three denticulations, the lateral only two. 
Although the file has passed for some depth into the sub- 
stance of the crown, yet the enamel, from its thickness, has 
scarcely been abraded sufficiently at the bottom of the notch 
to expose the dentine. (See figs. 1 and 2.) 
The practice of artificially interfering with the incisive 
teeth is one which prevails amongst various savage races in 
different parts of the world, but more especially amongst 
many tribes of negToes. In some, as in the case before us, 
it is the custom to give to the cutting edge a serrated ap- 
pearance ; in others, as in the people of Unyamuezi, described 
by Captains Speke and Grant, the lower incisors are more 
or less extracted, and a deltoid-shaped fissure is cut between 
their two upper central incisors. Winterbottom, again, de- 
scribes some of the negro tribes as filing their teeth, so as 
to make them conical and sharp-pointed ; whilst Livingstone 
states that both sexes amongst the Batoka negroes, a tribe 
living near the Victoria Falls on the Zambesi river, knock 
out the upper front teeth at the age of puberty, but leave 
the under teeth in their place. Amongst the Manganyas 
Dr Kirk tells me the practice of filing the upper incisors is| 
confined to the male sex. 
In the lower jaw of the skull of this Manganya negro, 
only the left lateral incisor is in its socket, the rest having, 
unfortunately dropped out of their alveoli, but it exhibits 
no marks of the file. The canine teeth are somewhat 
remarkably shaped at the cutting edge, where they exhi- 
bit a prominent central tubercle, with two faintly-marked 
lateral elevations. The intervals between the different teeth, 
though very perceptible, are yet scarcely so strongly pro- 
nounced as in the upper jaw. The vertical and antero- 
posterior diameters of the ascending ramus are almost ^ 
equal. The horizontal ramus is comparatively feeble, except 
at the symphysis, which possesses a fairly-marked chiu. 
