8 THE BEGINNINGS OF LIFE. 



we can notice is that the outer portion of its protoplasm is 

 rather denser than the inner, and is free from granules. In the 

 interior the protoplasm is much more fluid and is filled with 

 streaming granules. In this inner portion we observe a small 

 round or oval body called the nucleus, which is of diflferent 

 chemical composition to the surrounding plasm and in which the 

 vital activity seems to be centred, for it has been shown that if 

 the nucleus be removed the cell may still exhibit movement and 

 irritability, but can neither grow nor persist. In the diagram 

 also you will observe a space marked P.V., which stands for pul- 

 sating vacuole. Kindly remember that space for I shall refer to 

 it again presently. We see, too, that the creature slowly, almost 

 imperceptibly, puts out finger-like processes, which are techni- 

 cally called pseudopodia, or false feet. They may well be styled 

 fahc feet, for they are not feet at all ; they are simply prolon- 

 gations of the protoplasm, and they are drawn in in one place 

 and put out in another indiscriminately. By means of these 

 pseudopodia the ama^ba creeps in a sluggish diffluent way across 

 the glass, and it also uses them as tentacles to enable it to 

 capture food particles. This brings us to another interesting 

 phase of amoeba life — the way it takes its food. It is a way that 

 I have often wished that I could imitate myself when I have had 

 the toothache. A food particle comes in contact with the surface 

 of the cell, a process is put forth on each side of it, the processes 

 close round it and it is drawn into the centre of the cell, where 

 the nutrient matter is absorbed. You know the Yankee slang 

 phrase which represents a man as "getting outside of" his 

 victuals. The ama?ba realises that to perfection, and I have seen 

 it in its sluggish way " get outside of " an immense meal of 

 small things. Such aldermanic feeding powers cause the 

 creature to increase in bulk, and when such increase has pro- 

 ceeded far enough it sets to work to reproduce its species. This 

 is an equally simple process. A constriction appears in its 

 nucleus and gradually the cell divides into two cells, each of them 

 the counterpart of the original, though of course smaller in size. 

 It is on this account that Professor \Veismann has declared that 

 under favourable conditions the amoeba is immortal, that is, that 

 it would go on subdividing in this way indefinitely. But we now 

 know that this is not the case. After a certain number of 

 subdivisions the momentum seems to be lost ; and it appears to 



