422 ON THE FOSSIL BONES OF PACHYDERMATOUS QUADRUPEDS. 



The last molar tooth, A, differs from the five which precede it, in its 

 base being triangular, in there being no slope at its posterior edge, 

 and consequently in there being formed no second round or ova 

 fossette. 



With respect to the first molar tooth, it appears that it is always 

 smaller, and that its anterior angle is more acute ; it is also nearly 

 triangular, but in a different way from the last. . 



The internal surface of all these molar teeth presents above the 

 neck two conical and projecting portions, which are the extremities of 

 their two eminences ; externally they present a broad surface slightly 

 undulated, and marked towards the anterior third or fourth by a ver- 

 tical side, very little projecting, d, d, d. 



The differences of forms, which detrition produces, are much less 

 considerable in the inferior molar teeth. 



They consist of two eminences formed out into a portion of a cylin- 

 drical surface, a, b, fig. 5, and placed obliquely the one behind the 

 other; so that their concavity is directed inwards and a little forwards. 

 Detrition only enlarges the crescents of their summits ; but this figure 

 of double crescent , c, d, fig. 4 ; and e, f, g, h, fig. 2, is preserved, until 

 the eminences are worn to their base, at which period the tooth be- 

 comes rectangular and simple, i, k, /, fig. 4. 



The crescents are so much the more convex, and so much the more 

 obliquely placed, with respect to each other, according as they are ob- 

 served in a tooth placed more posteriorly. 



The anterior molars are placed in a slightly serpentine line. 



With respect to the incisors, the upper ones have the peculiar cha- 

 racter of being very much compressed and placed obliquely, forming 

 together in this case an angle of ninety degrees. The great inferior 

 teeth are truncated and nearly cylindrical in the individual now before 

 me : but I think it arises from the kind of life it was made to follow 

 at the Menagerie of Versailles, and that naturally they would be in 

 the form of an acute pyramid, as those of the unicorn rhinoceros of 

 Java. 



The senile or external upper teeth appear likewise to have been 

 compressed. 



The small intermediate teeth below are conical. 



Such are the teeth of a very old unicorn rhinoceros of India. I have 

 not had an opportunity of following their succession ; but I have no 

 doubt that in this respect what I shall soon have to say of the other 

 species is also applicable to this. 



3. The Vertehrce. 



There are 56 in all : 7 cervical, 19 dorsal, 3 lumbar, 5 sacral, 22 

 coccygian. 



The atlas (plate 41, figs. 27, 28, 29, and 30) has its transverse pro- 

 cesses very large, and very broad, and without obliquity ; so that their 

 contour is almost rectangular, which distinguishes them from the hip- 

 popotamus ; their very great size still better distinguishes this atlas 

 from that of the elephant. The spinous process is but a large tubercle. 

 There is under the body a small longitudinal ridge. 



The transverse processes of the axis are slender, pointed, and in- 



