HYDRA. 187 
divided from head to tail, the body no longer formed a tube, 
but in each of them was open the whole length on one side. 
Both parts, after being cut, lay in a state of collapse for 
about half an hour. The next day each was standing up- 
right, and spreading out its remaining portion of tenta- 
cula, and they ate night willingly a worm given to each 
of them. By the fourth day the wound, seemingly so 
deadly, was healed, and each was again tubular, and tenta- 
cula had begun to grow, to make up for those that were 
lacking ; and in a day or two more each formed as complete 
a polype as those that had never been subjected to the sharp 
work of the scissors. 
In the next experiment he was not quite successful. It 
required very delicate management, for it was nothing less 
than turning a polype inside out. A person would naturally 
have thought, that to any creature this would be completely 
ruinous,—that it would be quite impossible for any animal 
to survive under such an operation as turning it inside out, 
as one would do a glove or stocking. Yet M. Trembley 
gives us a detailed account of the ingenious manner in which 
he accomplished this, and, what is wonderful, that the 
polypes did not seem to be injured by it. It was plain, 
however, that they did not much like it, that they preferred 
