292 THE BEGINNINGS OF LIFE. 



been made, so that I was obliged to choose specimens 

 that were nearly divided, in order to observe the final 

 process of separation; and then I had to watch the 

 individual for from one and a half to two hours — 

 which I assure you was rather trying and tedious, as the- 

 active little beings were trotting about continually, and 

 I had to preserve them in a rather large live-box^ since I 

 found if they were confined too closely the division 

 would not occur. In Vorticella and Epistylis I have 

 seen the division in progress, but the process was so 

 slow that I never saw it through, and several times 

 when I had watched long they disappointed me, by 

 passing into the "encysted" state instead of com- 

 pleting the division. This may have been partly due to 

 their not having had fresh water enough to suit their 

 health.' Dr. Moxon adds : ^ I should say that, as far as 

 I have seen, the larger and more perfect Infusoria do 

 not increase very rapidly in numbers," — that is, by the 

 acknowledged methods of reproduction, fission, gem- 

 mation, and internal production of embryos. My own 

 experience is very similar to that of Dr. Moxon. I 

 have seen the process taking place in various ciliated 

 Infusoria, though by no means frequently, and when it 

 does occur, it has generally been very slowly brought 

 about ^. M. Haime, moreover, in speaking of the pro- 



^ I have seen it much more frequently, however, in the smaller flagel- 

 lated Infusoria {Monads). With them the fission may be either longitu- 

 dinal or transverse in its direction, and I have found the process occupy 

 at least fifteen or twenty minutes. 



