572 



MANATIS AND DUGONGS. 



sluggishness of its movements, when crossing its pond there was none of the lateral 

 movement of the body so characteristic of the seals. All flexions were up and down, 

 the whole trunk bending a little in that direction, the base of the tail doing so 

 freely at a clearly-marked transverse fold-line in that region. An opportunity 

 occurred for seeing it out of water, when its pond was drained dry for a short time, 

 From my observations on this occasion, it was perfectly evident that the manati is 

 purely aquatic in habits, and that it never willingly quits the water. When on 

 land, it seemed perfectly unable to advance or recede, the only movements it 

 performed being that from its belly to its back, and vice versa. The power of 

 moving the slightly exserted elbow was considerable, whilst that of the wrist was 

 small but apparent. It used its limbs much more freely than do the seals, some- 

 times employing the extreme margins of the paddles to assist in introducing food 

 into its mouth, at others employing them in progression along the bottom of the 

 pond, during which time the swimming tail could not be brought into play to any 

 extent." 



Beyond the fact that only a single young is produced at a time, there appears 

 to be no accurate observations as to the breeding-habits of the manati ; neither are 

 we acquainted with the length of time these animals can remain submerged. 



The flesh of the manati, which is very light in colour, is eaten by the natives 

 of the Amazon region, and is compared by Bates to pork. The fat is reported, 

 however, to have a disagreeable flavour. 



The Dugong. 



Genus Halicore. 



The dugong, or as it should properly be termed, from its Malayan name, duyong, 

 is a very different animal, both externally and as regards the structure of its skull 

 and teeth, from the manati. Externally, it is characterised by the nostrils being 

 situated on the upper part of the muzzle, by the tail being crescent-shaped and 

 concave posteriorly, and by the total absence of any trace of nails on the flippers. 

 The skull is characterised by the great thickness and massiveness of the beak and 

 the extremity of the lower jaw, both of which are sharply bent down, so as to form 

 almost a right angle with the long axis of the skull. The teeth grow throughout 

 life; and in the adult state comprise a pair of incisors in the upper jaw, and five 

 molars on each side of both jaws. In the females, the incisors are small and do not 

 pierce the gum, but in the males they assume the form of rather large and nearly 

 straight tusks, which are partially coated with enamel, and are directed downwards. 

 The molars are cylindrical in form, the last in each jaw being more complex than 

 the others, and looking as if it were composed of two cylinders joined together. 

 These teeth have no enamel ; and, as in the manati, some of the front ones are shed 

 before those behind come into use. There can be little doubt but that the molar 

 teeth of the dugong present one step in the process of degeneration which has 

 resulted in their complete disappearance in the northern sea-cow. In colour, the 

 dugong is either uniformly bluish grey, or the under-parts may have a more or less 

 distinct whitish tinge. The normal length attained by these animals varies from 



