AMCEB^A. 



19 



mouth nor anus. The food can be taken in and expelled at 

 any part of the body. This process can easily be watched if 

 particles of indigo are placed in the water surrounding an 

 amoeba : a speck of indigo will be found to be drawn to the 

 protozoan by the pseudopodium, and then it can be watched 

 gradually sinking into the protoplasm until it reaches the 

 endosarc, where it remains whilst the substance (if an organism) 

 is digested, the waste part being expelled through any part of 

 the animal. The food consists of organisms still smaller than 

 the amoebae are themselves. The granules in the endoplasm 

 are regarded as stages in the upward or downward metabolism 



Fig. 2. — ^MCEBA (groatly magnified). 



i. Large specimeD, showing structure, ii. A smaller specimen in process of division, 

 iii. Later stage of ii. a and n, nucleus ; b and cv, contractile vacuoles ; Fv, food 

 vacuoles; Psm, pseudopodia. (All greatly enlarged.) 



of the material of the body. Amoeba reproduces by the 

 primitive method of "fission" or division. The nucleus of 

 the amoeba divides into two (fig. 2, ii. and iii., a), and one of 

 these nuclei, surrounded by part of the original protoplasm, 

 breaks off and floats away ; thus one amoeba Vbecomes two. 



