10 MR. A. L. ADAMS ON THE OSTEOLOGY OF 
same small form. In this specimen all the characters of the Elephant’s tusk are well 
shown, the “ engine-turning ” being especially distinct. 
3. First or Preantepenultimate Milk-molar ; Second or Ante- 
penultimate Milk-molar. 
In all known species of the genus Hlephas both the first and the second milk-molar, 
theoretically, have two divergent fangs ; the only exceptions apparently are among the 
Maltese fossil Elephants, which show a functionally developed second tooth with only 
one straight fang, as seen in Pl. I. fig. 6, and others referred to by Falconer, and 
published in the sixth volume of the Society's ‘ Transactions”. 
With reference to the theoretical first or preantepenultimate milk-molar, rarely 
developed in either fossil or recent species, there is one very interesting specimen 
in the British Museum. 
The African skull containing this condition is No. 7086 of the osteological catalogue. 
It is the same referred to in the ‘ Fauna Antiqua Sivalensis,’ pl. 14. fig. 4, left side, @, 
and by Blainville in his ‘ Ostéographie,’ pl. 9. figs. 1, 2. The appearances of the 
dentition are as follows:—The milk-incisor and its enamelled tip is just protruding 
beyond the sheath, with a club-shaped -point as seen in the Zebbug fossil (Pl. I. fig. 1), 
the former being 1:4 inch in girth. In the Upprrr Jaw the second or antepenultimate 
is in full wear, with one ridge of the next tooth invaded. ‘The former is 0°8 by 0°7 inch, 
and composed of three plates and two talons; the latter is 2°3 by 1 inch, and is composed 
of five plates and two talons; behind all is the empty alveolus of the last milk-tooth. 
The Lower Jaw (Ricur) contains the antepenultimate and penultimate molars. 
The former is in full wear, with three ridges of the latter invaded. The antepenulti- 
mate is 0°8 by 0°4 inch ; its fangs are furcate, with a pronounced depression or pressure- 
mark below the crown posteriorly, as in the fossils to be described presently. The 
penultimate is 2-2 inches by 1:1 inch, and made up of six plates and two talons. 
The Lert Lower Ramus contains the first or preantepenultimate, composed of two 
plates and two talons ; the length of the crown is 0°65 by 0-4inch. The antepenultimate 
is also composed of two plates and two talons; its length is 0-85 by 0°6 inch. The fangs 
in both are divergent; but the posterior of the preantepenultimate is more divergent 
than either of the antepenultimate, and absolutely crosses the anterior fang of the 
latter, which, like the other root, is inserted more perpendicularly. The penultimate 
is of the same dimensions as that of the right ramus; and the same number of ridges 
are invaded. Vo septum divides the pre- from the antepenultimate, and the latter and 
the penultimate ; so that the grinding-surface on the left side is not more extensive than 
on the opposite. Indeed the three successive teeth are close together, whereas there 
is a septum between the ante- and penultimate teeth in the right side. Thus the 
additional tooth takes up the space of the ordinary septum. 
* Page 286, and pl. 53, fig. 2; see also Paleeont. Mem. vol. ii. p. 297. 
