Some Questions which they Suggest. 71 



success for the moment of its occurrence, and we look in 

 vain for the dead body. 



Whether of these two views be the more reasonable it 

 may be hard to decide. However that may be, it is certain 

 that there are unicellular bodies, such as the Diatoms, in 

 respect of which Weismann has so forcibly shown that 

 death cannot be thought of as a normal event. Thus out 

 of the depths and first rudiments of organic life there 

 crops up a suggestion of that immortality which is the 

 hope and aspiration of its very highest members. 



Then with regard to encystment. We have seen that 

 this occurs in two forms in the life-history of the myxies. 

 We have found that the single swarm spore may be encysted 

 and is then known as a microcyst, and that from this 

 condition it may be awakened and recalled to its activity 

 as a swarm spore, and we have found also that, in the form 

 of sclerotium, the whole plasmodium may become quite 

 dry and hard as an aggregation of cysts, and thus be 

 reduced to a condition of suspended vitality, but from this 

 also it may be aroused to its former powers of movement 

 and life as a plasmodium. In neither of these cases 

 do we find encystment to be associated with death, nor 

 with reproduction. " The essential characteristic of 

 encystment," says Weismann, " is a simple process of 

 rejuvenescence without multiplication." 



The length of time during which animation can be sus- 

 pended in the case of plasmodia is very remarkable. De 

 Bary found a plasmodium of Didymlwn serpula to move 

 after seven months' desiccation ; and a case is cited by 



