166 THE MEDUSA. 



in common with the class to which it belongs, God 

 has endowed it with a stinging power, which is 

 equal to all its necessities. No sooner does a fish 

 come in contact with this apparently helpless crea- 

 ture, than the medusa emits a fluid so pungent that 

 the victim is paralyzed and motionless, and becomes 

 an easy prey. 



The medusa may be seen to depress the margin 

 of its body, and to flap with its fringed membrane, 

 somewhat like the opening and shutting of a para- 

 sol, thus exerting its power of locomotion. The 

 movement referred to is performed about fifteen 

 times a minute, very regularly ; and by the reaction 

 of the water, the medusa is sustained at the surface. 

 It descends in the water by simply contracting its 

 substance in all directions ; and sometimes, to sink 

 more quickly, it turns itself over, so that the con- 

 vex part is uppermost. 



In some species, the young may be observed, at a 

 certain period, transferred from the ovaries on the 

 lower surface of the body. After changing in size, 

 colour, and form, they are clothed with cilia, and 

 then swim freely about. On one of them adhering 

 to some object covered with cilia, arms appear 

 about the mouth, and actively seek the needed 

 food. It now freely swims about till winter comes, 

 when it continues in quietude. At the approach of 

 spring, transverse lines appear on the surface ; these 

 deepen into furrows, dividing the body into several 

 portions, which, for a time, remain in contact, but 



