114 NATURAL HISTORY. 
that the prey of the animal is transfixed by it. It is, at 
any rate, a very powerful weapon, and the Narwhal has 
been known to thrust it into the oak timbers of a ship. 
This animal, formidable as it is, is often taken by the 
Greenlander, who obtains from it oil, food, weapons, and 
ropes. He uses the tusk in the manufacture of spears, 
arrows, hooks, ete. 
195. There is a family of Cetacea called the Dugong 
tribe, which is so aberrant that zoologists differ as to 
their proper place, some associating them, on account of 
their thick, tough skins, with the Pachydermata, and 
some placing them with the Cetacea. They are herbiv- 
orous, and not carnivorous like the other families of the 
Cetacea, living mostly on sea-weed. They have stiff mus- 
taches, and, when their bodies are partly out of the water, 
they have, viewed at a distance, a somewhat human ap- 
pearance, which has given rise to the “‘ mermaid” stories. 
These animals are called Sea-cows, Sea-calves, etc. One 
species, found in the Indian Seas, especially among the 
islands of the Indian Archipelago, is eighteen or twenty 
feet in length. In Fig. 95 you have the skeleton of this 
rh 
Ry ita OS en 
POR Sy 1 Ya Ta an 
Fig. 95.—Skeleton of Dugong. 
singular animal. It has, you see, no hinder extremities. 
The anterior extremities are paddles, like the flippers of 
the Whale; and the resemblance in the bones to those of 
the hand of man is very decided, the four fingers being 
present, and an attempt atathumb. There is an animal 
similar to this found on the coast of Mexico and of the 
northern part of South America. It is, however, smaller, 
