172 HISTORY OF BRITISH ZOOPHYTES. 



little animalcules swimming in it, though the longer he 

 observed them the more he was disposed to question the 

 correctness of this conjecture. 



One day he shook the jar in which they were enclosed, to 

 see what effect it would have on them. The result was very 

 different from what he expected. Instead of seeing the 

 body and arms agitated in consequence of being disturbed 

 by the motion of the water, the whole suddenly collapsed 

 into a little knob of green matter, and the arms quite dis- 

 appeared. He was greatly surprised ; but his curiosity being 

 increased, he continued to watch them, and while he was 

 observing them with a lens he saw them gradually expand, 

 so as to resume their former appearance. He began then 

 to be convinced that they were animals. The wonder was 

 that he had not sooner been assured of this, for nearly forty 

 years before they had been described as animals by Leeuw- 

 enhoek, and by an anonymous English naturalist, but as 

 their observations had not excited much attention, they had 

 escaped his notice. Nay, even now he was not thoroughly 

 convinced; for though they might resemble slugs that could 

 contract their body and their horns, why might they not 

 be a kind of sensitive plants, collapsing when they were 

 touched ? 



