116 LIFE AND DEATH. 



feature in the process is the rejuvenescence of the individual. This 

 rejuvenescence however is said to not only consist in the simple 

 transformation of the old individual, but in its death, followed 

 by the building up anew of another individual. ' The parent 

 organism and its offspring are two successive living stages of the 

 same substance separated, and at the same time connected, by the 

 condition of rejuvenescence which lies between them ' (1. c., p. 79). 

 An ( absolute continuity of life does not exist ' ; it is only the dead 

 organic matter which establishes the connection, and the ' identity 

 of this matter ensures heredity/ 



It is certainly surprising that Gotte should identify encystment 

 with a cessation of life, and we may well inquire for the evidence 

 which is believed to support such a view. The only evidence lies 

 in a certain degree of degeneration in the structure of the individual, 

 and in the cessation of the visible external phenomena of life, such 

 as feeding and moving. Does Gotte really believe that it is an 

 incorrect interpretation of the facts to assume that a vita minima 

 continues to exist in the protoplasm, after its complexity has 

 diminished ? Are we compelled to invoke a mystical explanation 

 of the facts, by an appeal to such an indefinite principle as Gotte's 

 rejuvenescence? Would not the oxygen, dissolved in the water, 

 affect the organic substance the life of which it formerly maintained, 

 and would it not cause its decomposition, if it were in reality dead ? 



I, too, hold that the division of the encysted mass is of 

 secondary importance, and that the encystment itself, without the 

 resulting multiplication, is the original and essential part of the 

 phenomenon. But it does not follow from this that the encyst- 

 ment should be considered as a process of rejuvenescence. What 

 is there to be rejuvenated? Certainly not the substance of the 

 animal, for nothing is added to it, and it can therefore acquire no 

 new energy ; and the forms of energy which it manifests cannot be 

 changed, since the form of the matter is just the same after quitting 

 the cyst as it was before. Rejuvenescence has also been mentioned 

 in connection with the process of conjugation, but this is quite 

 another thing. It is quite reasonable, at least in a certain sense, to 

 maintain the connection of rejuvenescence with conjugation ; for 

 a fusion of the substance of two individuals takes place, to a 

 greater or lesser extent, in conjugation, and the matter which 

 composes each individual is therefore really altered. But in simple 



