IV. MAMMALIA. 37 



The Dugong (HaUcore dugong) is found as far south as Moreton 

 Bay on the Queensland coast, and westwards through the Indian 

 Ocean to the east coast of Africa, inhabiting shallow waters of 

 bays and inlets and feeding on sea-weed. When adult it may 

 be as much as 10 feet in length ; the colour of the smooth 

 glossy back varies from flesh colour to light brown, the under 

 surface being lighter. The full-grown males have a pair of 

 conspicuous tusks in the upper jaws, which are not developed 

 in the females. The flesh is valued as food by the natives ; the 

 oil is of excellent quality, and has been used with good results 

 as a substitute for cod-liver oil ; but the number of the animals 

 is limited, and the fishery is yearly becoming less productive. 



The Rhytina— (-SAy^zwcfc s^eZ?e7-«) of Alaska. This species is now 

 extinct^ but a skeleton (not quite perfect), and some casts have 

 been obtained for this Museum. It was the largest of the Sirenia, 

 sometimes measuring 25 feet long. It was formerly abundant at 

 Behring's Strait. The head was small in proportion to the body. 

 The neck was short, the body rapidly diminishing behind. The 

 short fore arm terminated abruptly without fingers or nails, and 

 was overgrown with a short stiff brush of hair, the hind legs being 

 replaced by a whale-like fluke. The animal was destitute of 

 teeth, but instead was provided with two masticating oral 

 plates, one in the upper, the other in the lower jaw. * 



Order X.— EDENTATA.— The word Edentata is used 

 by naturalists to signify toothless mammals. This order in- 

 cludes the Sloths, Ant-eaters, etc., which are peculiar to South 

 America and Africa. The Sloths are animals with long curved 

 claws suited for tree-climbing, but not at all suited for walking on 

 the ground. Existing species seldom exceed three feet in length, 

 but in ancient times gigantic species existed, as witness the Mega- 

 therium (see Chapter XI Y. Palaeontology). The Anteaters have 

 long pointed snouts, and a narrow tongue which they shoot out 

 rapidly to a consideral^le distance to capture the ants, on which, 

 as their name implies, they feed. The Armadilloes are the most 

 remarkable of the Edentata. Their bodies are covered with horn- 

 like plates or scales, on the back and over the tail and joints, 

 while the bellies are only protected by ordinary soft hairy skin. 

 A few species of Edentata are found in other parts of the ^vorld 

 — the Pangolins of Asia, and the Aard-varks of Africa — but 

 they differ in many respects from the South American species. 



* Vojage of the Vega. Vol. 2, p. 272. 

 D 



