136 THE WORLD OF THE SEA. 
fund of reflection for the philosopher does this calculation open 
up. The meduse being light and floating, every current and 
movement of the water carries them farther and farther from the 
place where they were brought into existence. Some species, - 
upon which the whales live, are swept in myriads from the coasts 
of Mexico to the Hebrides, one of the principal stations of these 
enormous Cetacea. 
For a long time the acalephe were neglected by naturalists, 
who, like Réaumur, took them for masses of jelly, or a kind of 
gelatinised water; they little suspected that they were animal 
organisations. Constant Duméril conceived the idea of injecting 
milk into their cavities. He noticed that the liquid traversed nume- 
rous channels with great regularity, and he soon discovered the 
organs of digestion and of circulation. Ehrenberg found in one of 
the Aurelia a most unexpected and complicated structure: and at 
last science was aroused to dive into the mysteries of their internal 
structure. These studies as they are pursued become more and 
more marvellous, as we follow these living gelatines, these rude 
attempts at life, as they might well be called, forming and re- 
forming thousands of times before nature elaborates with their 
substance an animal of any solid consistency. 
The medusze are the food of small marine animals, principally 
of the worms and mollusks. The mouth is placed in the middle 
of the neck, and some of them have more than one mouth. These 
strange creatures are very voracious, and swallow their prey with- 
out masticating it, or even dividing it. When the animal it has 
captured offers resistance, the acalephz simply holds it fast and 
allows its victim to struggle until exhausted with fatigue. A 
medusa has been seen to seize an animal by its head, which, in its 
violent struggles to escape, completely turned its captor inside out. 
Some medusze imprisoned in a vase with small fish and little 
crustaceans were frequently seen to devour them; though their prey 
had a much higher organisation, and intelligence more than 
sufficient to perceive and to fly from danger. Apparently, says 
Forbes, the meduse have a democratic delight in destroying 
animals of higher classes. Thus in the ocean world there seems 
to exist the rivalry of caste. 
