16 DR. J. E. GRAY ON THE JAPANESE PIG. (Jan. 28, 
that of the common domestic Pig, in being shorter, and much higher 
in front, especially from the greater height of the front of the lower 
jaw at the gonyx; in the forehead of the skull being rather concave 
before the orbits, flattened, and furnished with a sharp-keeled edge 
on each side, producing a deep concavity on each cheek in front of 
the orbit ; in the palate being much broader for its length, and the 
series of the teeth wider apart and rather arched. 
In the height of the front of the skull, in the flatness of the 
nose in front of the orbit, in the concavity of the cheek, and in the 
broadness of the palate, the skull of the Japanese Pig bears some 
relation to the skull of the Potamocherus penicillatus ; but the late- 
ral ridges of the nose are not so dilated, while the skull is higher in 
front, and the palate is wider in the Japanese Pig than in the same 
parts of Potamocherus. ’ 
In the wild Pigs of Europe, India, and Java, and in the European 
domestic varieties, the nose of the skull is always narrow and rounded 
on the sides, and the palate is narrow. 
Under these circumstances, I am induced to regard the Japanese 
Pig as a distinct type, and propose to call it Sus pliciceps until we 
receive further information respecting it. 
We have in the Museum a very large and a moderate-sized skull 
of the domestic Pig, slightly differmg from the others, and from 
those figured by Cuvier and De Blainville, in the frontal bone being 
rather depressed and concave in front of the eyes; but we do not 
know the particular variety to which these skulls belong. Though 
they agree with the Japanese Pig in these two circumstances, they 
differ from it and resemble the skulls of the common Pigs and the 
Wild Boars of Europe and Asia in all other particulars, and show no 
other character in common with the Japanese Pig, which is also 
characterized by its peculiarly wrinkled face, well represented in the 
figures of these animals published in the ‘ Proceedings of the Zoolo- 
gical Society ’ 1861, p. 263, and the ‘Illustrated News’ January 11, 
1862, p. 49. 
The species at present is only known in its domesticated state. 
It may perhaps be the descendant of a species found wild in the 
valleys of the islands. 
In both these skulls of the domestic Pigs the lower jaws are rather 
higher than usual, particularly at the gonyx; and this is especially 
the case with the largest skull, which is said to be that of an old 
Boar. Can the size of the lower jaw be a peculiarity of the male sex? 
We have not sufficient materials to determine this question, either in 
the Museum or in the plates that have been published of the skull 
of the genus Sus. 
I may further observe, there is considerable difference in the occi- 
put between the European and the Japanese Pig; the processes of 
the back of the palate are much more erect in the Japanese Pig 
than in the European and Asiatic Pigs, wild and domesticated. 
Though I have only described this animal as a species, it evidently 
forms a section in the genus by itself. The restricted genus Sus 
may be divided thus :— 
