MAMMALIA. 
23 
nostrils, where it terminates in a straight line, leaving the tip of the muzzle 
naked. 
In. Lines. | In. Lines. 
Length from nose to root of tail . . 31 0 j 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 bull® 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 bullae 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 triangular 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 
