MAMMALIA. 



2.'} 



nostrils, where it terminates in a straight line, leaving the tip of the muzzle 

 naked. 



In. Lines. I In - Lines - 



Length from nose to root of tail . . 31 | Length of tail 14 3 



Habitat, Chonos Archipelago, {January.) 



The Chile Otter was originally described by Mr. Bennett from a specimen 

 presented to the Zoological Society by Mr. Cuming, but as this specimen is a 

 young animal, scarcely half-grown, it does not present some of the characters of 

 the species in so marked a manner as the adult. I have, therefore, availed myself 

 of an adult specimen in Mr. Darwin's collection, to draw up the above de- 

 scription. 



Compared with the Common Otter (Lutra vulgaris, Auct.) the most striking 

 difference consists in the character of the fur: the hairs instead of being ad- 

 pressed as in that species, are here semi-erect, and appear as if they had been 

 clipped at the extremity. The fur is of a deeper colour, but has a slightly grizzled 

 appearance, owing to the tip of each hair being of a much paler colour than the 

 remaining part. 



In the young animal described by Mr. Bennett, (which in weight was pro- 

 bably not more than one-third of that of the present animal) the hairs of the body 

 are of an uniform deep brown colour ; hence, if I am right in considering Mr. 

 Darwin's animal as the same species, it would appear that the grizzled character 

 of the fur is dependent on age. 



The semi-erect fur will also serve to distinguish the present species from the 

 Lutra Platensis ; the fur is likewise longer, the tail is shorter, and the feet are 

 smaller in proportion. The most important distinctions, however, are furnished 

 by the skulls ; I will, therefore, compare them. 



The skull of L. Chilensis compared with that of L. Platensis, (Plate 35, 

 figs. 4.) when viewed from above, presents but little difference in general form ; it 

 is, however, smaller in all its proportions, and the zygomatic arch is a little less 

 convex : the palate is proportionately shorter ; the tympanic bullae are much 

 smaller, less elevated, and wider apart, in which respect there is a greater ap- 

 proximation to the skull of L. vulgaris than to that of L. Platensis ; but here, the 

 tympanic bulla? are larger than in L. Chilensis. Both in L. Chilensis and Pla- 

 tensis, the sub-orbital foramina are kidney-shaped, the emarginated portion being 

 downwards, whilst in L. vulgaris they approach somewhat to a triangulur figure, 

 the apex being external. In L. Chilensis, however, this foramen is comparatively 

 larger than in L. Platensis, and the outer portion of the foramen forms the 



