154 THE WORLD OF ANIMAL LIFE 



These fringed plates are used for catching their prey. The 

 whales from which whalebone is obtained have very narrow 

 throats; and, although they are such enormous animals, they 

 cannot swallow anything larger than such creatures as shrimps, 

 small jelly-fish, and the young of crabs and lobsters. 



These small creatures always live in large shoals, and are 

 caught by the whale in a very remarkable way. Opening its 

 great jaws as widely as possible, it swims rapidly through the 

 shoal, the water rushing through its mouth the while, and the 

 fringed whalebone sifting out the tiny victims; until, the animal's 

 mouth being full, it closes its jaws and swallows them at leisure. 



The whalebone, therefore, forms a kind of sieve, which sifts 

 the whale's food from the water. 



We must not think, however, that all whales have such narrow 

 throats, and feed upon such tiny prey ; for some catch and swallow 

 quite large fishes. These have no whalebone, as it is not 

 required by them. Instead they have a number of stout, strong 

 teeth, with which to seize and hold their slipper)^ victims. 



Some savage tribes set a great value upon these teeth. One 

 chief, indeed, has been known even to make war upon another, in 

 order to obtain possession of a single whale's tooth ! 



The spermaceti whale is one of the toothed whales. It is 

 called the " spermaceti " or " sperm " whale because we obtain 

 from it the spermaceti " wax " which is so much used for making 

 candles. 



This spermaceti is mainly found in two large cavities in the 

 upper part of the whale's head ; not in the form in which we know 

 it, but as a kind of thick, oily liquid, which can be baled out in 

 buckets. The sailors procure it by cutting a hole in the top of 

 the whale's head, and letting down a bucket, just as if they were 

 drawing water from a well. A single whale will sometimes yield 

 as much as twenty large barrels of this valuable oil from the 

 head, and from seventy to a hundred barrels of oil altogether. 



When this oily liquid has been drawn off, it is allowed to stand 

 for a time. Before long the spermaceti separates from the oil, 

 and is soon firm enough to be taken out and put into a separate 

 vessel. 



