JSieiv Genus of Mammalia called Hydrcmiis. 33 1 



in regard to the. mus coi/pus, which Gmelin made from the 

 account of that Jesuit. M. Gruvel in the French trausla^ 

 tion njust, then, have omitted this iniportant character. 



However, the following are the observations, in lecrard to 

 the teeth, which I made in the two species of New Hoi- 

 land. 



These molar teeth present themselves first in a numlwr 

 worthy of remark : there are only two on each side, which 

 carries the whole numlxr to eight. Their form exhibits no 

 less singularity : the length of each is double its breadth : 

 the enamel traverses it in the middle, turning round in such 

 a manner, that the section forms pretty nearl^r the fio-ure S, 

 which is rendered sensible in particular by two excav'ations . 

 pretty deep, corresponding to the vacant spaces which exist 

 in that figure. 



The fe^ of the hydromis have Cwq toes ; those of the fore 

 feet are very short, and almost entirely enveloped : the other 

 toes are free. On the other hand, those of the hind feet 

 are engaged in a membrane : the external toe only is at 

 liberty, because the general membrane which extends over 

 it, and uhich borders the interior side, arises only I'rom the 

 extremity of the metacarpian bone of the annular toe ; it 

 forms on the last a small interior border, which does not 

 retain it in its deviation- The nails are compressed, pretty 

 long, hooked, and very sharp. 



The head, as far as could be judged from the remains 

 w hich I examined, is^ broad and depressed like those of the 

 beaver and the water-rat ; the muzzle appears to be less 

 obtuse ; the neck is thick and short j the ears squall and 

 rouad ; the whiskers long and thick. 



The hair is of two kinds, as i^i the beaver ; under the Ion<r 

 silky hair is a short felt, thick, and exceedinaiy fine. ° 



The hydromis has a resemblance also to tlfese animals by 

 the proportions of its body, andparticularlv by the short- 

 ness of its paws ; but they differ sensiblv by the' form of the 

 tail, which is almost as long as the body,' perfectly round, 

 and terminating in a point. 



In general, there can be no doubt that in the natural- 

 order theie animals ought to occupy an intermediate place 

 between the beaver and the water-rat: beino- destitute of 

 membranes on the hind feet, they would naturally belong 

 to the tribe of the latter; or, if their tail had the' form of 

 that of the beaver, they might be united with the species of 

 tliat genus. 



1st. The Ilydrom-i Coypou. — I have ^aid that it was first 



made 



