164 VITALISM AND SCHOLASTICISM 



the latter finds examples even of its major 

 manifestations both amongst vertebrates and 

 invertebrates. 



Over the phenomena as exhibited in the 

 vegetable kingdom we need not delay, for most 

 people will be familiar with the manner in 

 which begonias may be propagated by means 

 of very small portions of the parent plant, 

 from which entire specimens are reconstructed, 

 and everybody, however ignorant of horticul- 

 ture, must have seen cuttings being " struck," 

 that is to say fragments of a plant, say a 

 carnation, set in the ground and gradually 

 constructing for themselves roots so as to 

 become complete plants. 



It will be more interesting to devote the 

 space which can be allotted to this part of the 

 subject to a consideration of some instances 

 from the animal kingdom and we may com- 

 mence with the classical instance of the Hydra. 

 Hydra * The Hydra is a small fresh-water creature, 

 of a bright green colour and somewhat resemb- 

 ling a sea anemone, though very much smaller 

 and of a more elongated build. It was on this 

 creature that Abraham Trembley (1700-1784) 

 carried out his classical experiments in 1740, 

 showing first of all that if the polyp was cut 

 into two pieces each of those two pieces became 

 a new and complete polyp. 



