Ba 
Mr. C. Forster Cooper on Metamynodon bugtiensis. 619 
2,3,and 4. From the extent to which they are worn, the 
last premolar being rather more worn than the first molar, 
and trom the fact that the last molar is only just appearing, 
they might reasonably be considered as milk-teeth. Fortu- 
nately, however, there are in the collection two other 
specimens of the three anterior teeth absolutely similar in 
size and shape, but one of them rather more and the other 
rather less worn than those of the type-specimen. These 
two specimens have been sectioned, and neither of them shows 
the slightest indication of any replacing teeth. Specimens 
of comparable age of other forms of rhinoceros from the same 
deposits show that the fourth premolar comes into full wear 
after the first three and at the same time as the third molar, 
and from this point of view the series might be read as four 
premolars and only two molars ; but, if this were the case, 
the third molar should at least be ready to erupt, which shows 
that the reading of the last tooth of the series as the third 
molar is correct. It would appear further that, although the 
fourth premolar comes into use later than the first molar, 
and although for a period it shows less wear than the first 
molar, the wear soon equalizes, and then even reverses. 
This condition is clearly shown by a young adult specimen 
in the University Museum of 2. sumatrensis, where the third 
molar is Just touched by wear and the last premolar and first 
molar equally worn. » 
The specimen is broken away in front of the anterior teeth, 
but there is enough of the alveolar border remaining on one 
side to show that there was no tooth anterior to the series. 
The assumption, therefore, that the teeth represent three 
premolars and three molars may be taken as being very 
probable. If this is the case, then the shape of the last 
molar prevents this form from being placed anywhere except 
in the neighbourhood of the genus Amynodon. The three 
molars consist of a simple protoloph and metaloph with 
strong protostyle and metastyle on the ectoloph, the meta- 
style on the third molar being as strongly marked as on the 
others, A small crochet is present on the metaloph of the 
second and third molars, but only towards the top, and would 
soon disappear in wear. ‘This has happened on the first 
molar, if one was present. Of the premolars, the third and 
fourth are molariform. An internal cingulum is present and 
complete on the first two premolars and on the protoloph of 
the remaining teeth. 
The length of the six teeth is 280 mm., of which the 
molar series takes 196 mm. ‘The proportional lengths of the 
premolars and molars is thus not much oe to those 
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