32 On a new Genus of Mammalia, 



is the first time that the combination of ten and six incigori 

 has been met with among the mammalia : the last incisor 

 below is a little broader than the rest, and is half divided 

 bv a small groove. 



All the nirtrsupials are able, more br less, lo assist them- 

 selves readily with their tail : on the other hand it does 

 not appear {hat the peramehs can employ theirs for any 

 thing ; it is too siiort, is covered with short hair, and is 

 desiitute of the faculty of prehension. 



Their muzzle, which is much too long, gives them an 

 air exceedingly stupid ; but this dismal and disagreeable 

 phvsi(5gnomy is compensated by the lightness of their 

 motions, and the gracefulness of their gait, since they have 

 the posterior extremities twice as long as those before. I 

 have already remarked that tlie form of ihcir hind feet has 

 some analogy to that of the kaiiguroos. This dispropor- 

 tion between the paws gives them a greater similarity : it is 

 indeed so great that I have no doubt that they possess the 

 njcnus as well as the latter of raisinii' themselves on their 

 hind legs, and of using them to take leaps almost as ex- 

 lensive. 



In the last place, it isprol)able that the organs of genera- 

 tion of the perameles, while tlicy exhibit tlial analogy of 

 I'orm which characterizes all the marsupials, might have 

 afforded some generical diflerences, but I had no oppor- 

 tunity of examming them. 



These considerations, however, on which I have here 

 enlarged, seem to me to require the establishment of a new 

 family of the peramelts, in the natural order between the 

 didclpha and the kanguroos. 



Description of fhe Sprcirs. 



This genus hitherto has been composed v)f two species : 

 that published bv Dr. Shaw, under the name of didelphis 

 vbaula^ and another v.'hich is new, and to which I have 

 given the name of nasiiia. 



I. Pcicnncles nasula. (Plate I.) The length of the 

 rtuizzle'aiid nose of this pcramele forms its prmcipal cha- 

 racter ; measured from the extremity of the lip?; to the root 

 of the tail, its length is 0*-!5 metre; its head O'll metre, 

 and its tail 0*16 metre: its anterior extremities are 0*]8 

 metre, and its posturior ()*lG metre. 



It? liT-t incisor, tlie canine tooth, and the first molar, 

 Instead of being contiguous, are very ntuch separated from 

 each other, and hence ihc areat length of tlie muzzle. 

 The cutting molars arc lobed and have three points j those 



in 



