ELEPHAS PRIMIGENIUS.—HUMERUS. 
153 
instances where the groove was fully as open as in the African. Looked upon, however, 
generally, the above is fairly reliable in the diagnosis of the two species. 
4. As to degrees of saliency of the supinator ridge; individual instances in the Asiatic 
appear precisely to accord with 708h of the African. The ridge was less salient in many 
instances of the former, but here again there seems so much variability that one is not 
disposed to place much reliance on this character. Compare fig. 4 with 5. 
5. The ridge proceeding from the supinator upwards and backwards to the epiphysis 
is very often so pronounced in the Asiatic as to form a carina at its upper part, and would 
be of value if invariably persistent, but it is not so, being sometimes, as in 708h African, 
lost before it reaches that point. Compare fig. 4 a with 5 a. 
6. As to the position of the nutritive foramen, when one is present and of conspicuous 
size to entitle it to be considered the main opening, there appears considerable incon¬ 
sistency as to its exact position in the Asiatic Elephant, but when at all pronounced it is 
usually in a line with the apex of the supinator ridge, whereas in 70Sh it is in the 
lower third. In fossil specimens it is so frequently obliterated by mineral infiltra¬ 
tions as to be quite undiscernible; moreover, the multiplicity of these canals on various 
parts of the shaft, and their agreement in size, make it uncertain which to rely upon as 
the normal condition. 
7. With reference to the configuration of the distal articular surface, the following 
points are referred to by Busk, 1 which, if persistent in the African, as they are in all 
adult humeri of the Asiatic I have examined, would be invaluable in establishing specific 
characters. These refer to the (a) contours of the outer condyle; (b) the configuration 
of the arc formed by the lower border of the articular surface ; and (c) the contour of 
the trochlear depression posteriorly, as shown in his monograph referred to on the 
Maltese fossil Elephants. 1 
The above characters are, viz.: 
( a ) A more globose margin and general contour of the external condyle in the African. 
This is pronounced in 708h, whereas the same parts are less rounded in the Asiatic. 
Compare fig. 5 b with fig. 4 b. 
(b) The arch of the lower border formed when the humerus is placed erect on a level 
surface is shorter and nearly central in the African, whereas in the Asiatic it commences 
gradually from the margin and extends from nearly one to the other. Compare fig. 5 b 
with fig. 4 b. 
(c) The trochlear depression below the pit is narrow in the Asiatic, with nearly 
perpendicular sides, whereas it is shallow in the African, with gently undulating margins, 
in fact, as in the case of the bicipital groove, the one is deep and narrow, and the other 
broad and shallow. Compare fig. 4 b with 5 b. 
8. The depth of the olecranon pit and the hollow surface above it are seemingly 
greater in 708h African than I have seen in the Asiatic. These, however, may be con- 
1 ‘Trans. Zool. Soc. London,’ vol. vi, p. 257. 
