50 MOVEMENTS OF BIOPLASM. 



!!. Movements of bioplasm. One characteristic of 

 every kind of living matter is spontaneous movement. 

 This, unlike the movement of any kind of non-living 

 matter yet discovered, occurs in all directions, and 

 seems to depend upon changes in the matter itself, 

 rather than upon impulses communicated to the par- 

 ticles from without. I have been able to watch the 

 movements of small amoebae, which multiplied freely 

 without first reaching the size of the ordinary indi- 

 viduals. I have represented the appearance under a 

 magnifying power of 5,000 diameters of some of the 

 most minute amoabae I have been able to discover. 

 Several of these were less than Too T 000 th of an inch 

 in diameter, and yet were in a state of most active 

 movement. The alteration in form was very rapid, 

 and the different tints in the different parts of the 

 moving mass, resulting from alterations in thickness, 

 were most distinctly observed. In these movements 

 one part seemed, as it were, to pass through other 

 parts, while the whole mass moved now in one, now 

 in another direction, and movements in different 

 parts of the mass occurred in directions different 

 from that in which the whole was moving. What 

 movements in lifeless matter can be compared with 

 these ? 



18. Changes ending in formation of a capsule. 

 The movements above described continue as long as 

 the external conditions remain favourable ; but, if 

 these alter and the amoeba be exposed to the influence 

 of unfavourable circumstances as altered pabulum, 

 cold, &c. the movements become very slow, and 

 at last cease altogether. The organism becomes 

 spherical, and the trace of soft formed material upon 

 the surface increases until a firm protective covering, 

 envelope, or cell-wall, results. In this way, the life of 

 the bioplasm is preserved until the return of favour- 

 able conditions, when the living matter emerges from 

 its prison, grows, and soon gives rise to a colony of 



