482 PROFESSOR OWEN ON THE DENTITION OF PHACOCHCERUS, 
of the first set, or above them in the upper jaw ; and also that the subsequent shed- 
ding of the teeth in advance of the last large grinder was not in the order in which 
they are pushed out in the Elephant, the Wart-Hogs deviating very remarkably from 
that and all other quadrupeds in this respect. 
In the course of subsequent researches and comparisons, I have determined the 
original specimens in the British Museum and that of the Royal College of Surgeons, 
which were drawn and engraved to illustrate Home's paper, by which I have ascer- 
tained that the drawings were taken from two distinct species of Phacochcerus ; and 
I have been able to detect certain inaccuracies in the reduced figures in the engravings, 
which give countenance, not afforded by the specimens themselves, to the ideas of 
the mode of succession of the teeth described in Home’s paper. I propose, therefore, 
to give a more precise description of the subjects of the beautiful engravings, tab. 
xviii. and xix. of the Philosophical Transactions for 1799, and to add the additional 
facts and illustrations of the peculiarities of the dentition characteristic of the two 
species of Wart-Hog, and which determine the true number, kinds and succession of 
the grinding-teeth in both species. 
Tab. xvii. (Philosophical Transactions, 1799) gives a view of the skull of an old Pha- 
cochoerus Mliani, Van der Hoeven, the common species of Nubia, Abyssinia, Senegal 
and Cordofan, and sometimes called the North African Wart-Hog. It is well charac- 
terized by having, when fully grown, six functional incisors in the under jaw and two 
incisors {i. 1.) in the upper jaw, together with forms and proportions of the other 
teeth, which will be subsequently adverted to. The characteristic incisors are suffi- 
ciently indicated in the figure ; the large posterior grinders are alone retained in the 
molar series of both jaws. 
Tab. xix. fig. 1 (Philosophical Transactions, 1799) gives a view of the cranium of 
a younger individual of the Phac. Pallasii, Van der Hoeven, the Wart-Hog most 
common, though not peculiar to the Cape and the Guinea coast districts. The molar 
teeth which are exposed in this figure are, taking them from before backwards, the 
last premolar, the symbol of which is jo 4; the first true molar, m 1; the second true 
molar, m 2; and the last true molar, m 3. 
The teeth are drawn somewhat reduced in size, but not in a just proportion to the 
reduction of the size of the cranium and of the upper tusks ; nor are the relative 
lengths of the crown and fangs correctly given. The crown of the first true molar, 
e. g., is represented of the same length as that of the fourth premolar which precedes 
it, and nearly of the same length as that of the second true molar, whereas in the 
original specimen it is much shorter in consequence of having been longer in use. 
Had the differences which these teeth actually show in the extent of the abrasion of 
their respective crowns been appreciated and duly considered, it might have excited 
the suspicion that the second tooth, with an almost exhausted crown and much- 
absorbed fangs, would be shed before the first tooth, the summit of whose long, obtuse 
and cement-covered crown had only recently been subject to the wear of mastication. 
