82 MAMMALIA. 



were it not that those from the straits of Magellan seem to differ from such 

 as are taken at the Aleutian islands. 



Tkichechus, Lin.(l) 

 The 3Iorse resembles the Seal in its limbs, and the general form of the body; 

 but differs widely from it in the teeth and head. There are no incisors nor 

 canini in the lower jaw, which is compressed anteriorly to pass between 

 two enormous canini or tusks, which issue from the upper one, and which 

 project downwards, being sometimes two feet long, and of a proportionable 

 thickness. The enormous size of the alveoli, requisite for holding such 

 tremendous canini, raises up the whole front of the upper jaw, giving it 

 the shape of a huge inflated jowl, the nostrils looking upwards, and not 

 terminating the muzzle. The molars are all short, obliquely truncated 

 cylinders; there are four of them on each side, above and below, but, at a 

 particular age, two of the upper ones fall out. Between the canini are 

 two incisors, similar to the molars, which most authors have not recognised 

 as such, although they are implanted in the intermaxillary bone. Between 

 these again, in the young animal, are two more small, pointed ones. 



The stomach and intestines of the Morse are very similar to those of the 

 Seal. It appears that/wcus constitutes part of its food, along with animal 

 matters. One species only is as yet ascertained, the 



Trich. rosmarus, L. (The Sea Cow. ) It inhabits the Arctic seas, sur- 

 passes the largest Ox in size, attains the length of twenty feet, and is cover- 

 ed with a short yellowish hair. It is sought for on account of its oil and 

 tusks; the ivory of which, although rough grained, is employed in the arts. 

 The skin makes excellent coach braces. 



ORDER IV. 



MARSUPIALIA. 



So many are the singularities in the economy of the Marsupialia 

 or pouched animals^ as they are termed, which we formerly placed 

 at the end of the Carnaria as a fourth family of that great order, 

 that it appears to us they should form a separate and distinct one, 

 particularly as we observe in them a kind of representation of three 

 very different orders. 



The first of all their peculiarities is the premature production of 



(1) Trichechus, from rg}^ (hair), a name invented by Artedi for the Sea 

 Cow. 



