40S ON THE FOSSIL BONES OF PACHYDERMATOUS QUADRUPEDS. 



These teeth might be more easily confounded than the others with 

 the analogous teeth of the wild boar ; nevertheless, they may he dis- 

 tinguished from them by their angles being more blunt and their curves 

 more decided. 



The upper canine teeth of the hippopotamus leave room for less 

 doubt, as they are more obliquely worn on the side of their convexity, 

 rounded off in all parts, cut by a deep longitudinal furrow on their 

 internal surface, and by a slighter one on their external surface; they 

 do not resemble those of any other animal. My little animal has fur- 

 nished me with a well characterised section of one of these : it is 

 the end of the tooth; w r e may there observe the two furrows, and the 

 surface produced by detrition. The dimensions are again precisely 

 one half of those of the living sjDecies. f See plate 33, fig. 6). 



Fig. 9 is a fragment which appears to me to have belonged to an 

 intermediate upper incisor : however, it shows a difference from that 

 of the ordinary hippopotamus. The worn part, a b, is here convex, 

 while it ought to be concave. 



The furrow, b c, does not exist in that of the hippopotamus. 

 In addition to this, I give (fig. 4, plate 33) the germ of a grinder, 

 to which there is no corresponding germ in the ordinary hippopotamus. 

 It presents two knobs, the second of which is forked ; consequently it 

 has three denticuii, all very sharp. This is one of the. anterior molars, 

 which this small hippopotamus must have had more complicated than 

 the living species. It is 0..02 in length, and 0,01 in breadth at the 

 back. 



I was too firmly convinced of the immense influence which the form 

 of the teeth must exercise over the rest of the organization, not to feel 

 persuaded before hand, that all the other bones of this animal would 

 bear the same resemblance to the corresponding bones of the common 

 hippopotamus, as that observed in the teeth; however, I felt extremely 

 gratified to have it in my power to give the world a new proof of the 

 infallibility of those general 1 laws of zoology; and I used the utmost 

 diligence in disengaging those portions of the bones in which I per- 

 ceived the remains of characteristics. 



Every one of them, without a single exception, furnished a confirma- 

 tion of what had already been announced by the teeth. 



Thus, the fragment of the lower jaw (plate 33, fig. 8), although 

 very much mutilated, is not too much so, not to be easily distinguish- 

 able by itself. We may observe at a, that the inferior edge begins to 

 descend, in order to form that crotchet which is so characteristic in 

 the lower jaw of the hippopotamus ; and, at b, we may observe that 

 the slope between the coronoid apophysis, c, and the condyloid,- which 

 is wanting in this fragment, must have been of very inconsiderable 

 depth, as is the case in the hippopotamus. The salient line, d, the 

 different convexities, concavities, and fiat surfaces of this specimen, 

 are in a word identical with those of the same part of the large animal 

 with which I have compared it. The distance of the edges from a to 

 d, is 0,045. The hippopotamus, measured in the same place, gives 

 0,12, that is two and two thirds more. 



I have found, in the block of M. Journu-Aubert, another portion of 

 a lower jaw, more important than the former in many respects (plate 

 34, fig. 3) : it is that of the opposite side. It contains the last tooth, 



