76 THE SEA-SHORE 



whale catches the zoeas. When it meets with 

 a shoal of these little creatures it opens its huge 

 mouth wide, and swims through them. Then it 

 nearly closes its jaws, and lets down the whale- 

 bone plates, so that the hairy fringe forms a 

 kind of strainer all the way round. It then 

 squirts out the water from its mouth through 

 this fringe, which allows the water to pass 

 through it, but keeps back the zoeas ; and when 

 it has got rid of all the water it closes its mouth 

 completely and swallows the zoeas, a few thousand 

 at a time, after which it opens its jaws again, 

 and swims through the shoal once more. 



Doesn't it seem strange that the biggest animal 

 on earth should feed on some of the very 

 smallest ? 



PLATE XXV 



CRAB CHRYSALIDS (3 and 3 A) 



When the caterpillar of an insect has reached 

 its full size it throws off its skin and appears 

 as a chrysalis, or pupa. And the caterpillar, or 

 zoea, of a crab does exactly the same thing. It 

 casts its skin, and appears in quite a different 

 form. Only we do not call it a chrysalis, as a 

 rule. We call it a " Megalopa." 

 The word "megalopa" means "a creature with 

 big eyes," and it is given to the crab chrysalis 



