262 RAMBLES OF A NATURALIST. 



secrated two years of unremitting labour. This 

 animal resembles the finger of a glove with its 

 aperture surrounded by long, hollow, flexible, and 

 contractile prolongations. These organs serve the 

 polype like so many arms, enabling it to seize larvae 

 and other small aquatic animals, which are rapidly 

 digested after their introduction into the cavity of 

 the body. Let us take the moment in which it has 

 just swallowed one of these larv^, and, proceeding 

 with caution, let us try to tear it away. Rather than 

 relinquish its prey, the polype will suffer itself to be 

 turned inside out like the finger of a glove, to which 

 we have already compared it, when that which 

 formed the exterior skin will become a membrane 

 clothing the digestive cavity, and vice versa. Yet 

 the animal is none the worse for this ; it will remain 

 on the watch, seize and digest its prey precisely as 

 it did before. Let us go still farther ; let us cut this 

 Hydra into twenty or thirty pieces, and still each of 

 these fragments will continue to be nourished. They 

 will soon begin to grow, and in the course of a few 

 days we shall have twenty or thirty complete Hydras 

 obtained by this apparently barbarous process. 



With these incontestable facts before us we must 

 admit, that in these simple beings the function is 

 independent of the organ — that is to say, that each 

 part of the body is equally adapted simultaneously 

 to perform all the physiological acts ; but it is at the 



at Paris, devoted himself with much perseverance to the study of 

 the lower fresh-water animals. We are also indebted to him for 

 several curious observations on the embryology of some of the 

 terrestrial molluscs. 



