THREE EXTINCT SPECIES OF ELEPHANT. 269 
it would seem, is developed from a distinct point of ossification, or remains much 
longer in the condition of cartilage than in most other animals. It is also further 
evidenced in the condition of the internal calcaneal facet, which is not yet formed into 
a single articular surface, but consists of two small ones, separated by a shallow depres- 
sion—exhibiting in fact exactly the same condition as that shown in M. de Blainville’s 
figure of the under surface of the astragalus of /. africanus, and regarded, apparently, 
by that author as a distinctive character between the Indian and African astragalus. 
In truth, however, it only indicates an immature condition, since in the mature African 
astragalus no trace of such a division of the facets exists, any more than it does, I 
believe, in any other species. It isnot improbable, nevertheless, that the completion of 
this articular surface may be effected later in the African than in the Indian Elephant ; 
for in a very young astragalus of the latter the surface in question is quite entire. 
And as this, from other circumstances, seems to be an astragalus of about the same 
age as the Maltese specimen, it may be supposed that the latter may have resembled 
the African in the comparatively late completion of the internal calcaneal facet. 
In its general form the astragalus strongly resembles that of a young Indian Elephant in 
which the internal tuberosity is still unossified. The chief peculiarity observable in it, 
irrespective of the proportionate dimensions of the different parts, is in the existence of 
a large and deep pit towards the anterior part of the sulcus for the interosseous or 
calcaneo-astragaloid ligament: no such pit exists in any other astragalus that has come 
under my notice. But it may, of course, be merely an individual peculiarity. In the 
comparative length of the neck the bone resembles the Indian rather than the African 
astragalus, the upper edge of the scaphoid facet projecting in front of the middle of 
the anterior border of the tibial facet exactly one-half of the median antero-posterior 
diameter of that facet. 
With regard to the proportionate dimensions of the bone in its various diameters, and 
of the different facets as compared with the same measurements in the existing species, 
in most particulars no marked difference is observable, as will be seen from the measure- 
ments in Table IV., from which it will also be perceived that with respect to its somewhat 
greater proportionate breadth, again, the astragalus of /. falconeri shows a resemblance to 
the Indian rather than the African type. But in the proportionate dimensions of the 
various facets rather more important differences are observable. For instance, whilst 
in the Indian astragali, measured by me, the mean vertical diameter or height of the 
scaphoid facet, as compared with its length across, was about as 626, and in &. africanus 
as 602 to 1000, in #. falconeri this dimension is not more than 500. And, again, 
whilst in the Indian Elephant the antero-posterior diameter of the tibial facet stands in 
relation to its transverse diameter as about 758 to 1000, and in Z&. africanus as 900, in 
the mature £. falconeri it is 941, showing a rather remarkable difference, more especially 
from the Indian species. But of all these differences the most striking appears to be 
in the transverse or longest diameter of the scaphoid facet, which, in the Indian and 
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