RH1ZOPODA. 23 



(pseudopodia) from various parts of the body, as if it 

 were falling apart ; then it retracts these transparent feet 

 and becomes perfectly smooth and rounded, resembling a 

 drop of slimy, mucous mat- 

 ter. The body-mass is di- 

 vided into a clear cortical and 

 a medullary, granular mass ; 

 the outer highly contractile, 

 the inner granular portion 

 acting virtually as a stock of 

 food. These granules, like 

 the grains of chlorophyll in 



Vegetable cells and in dia- tionof the granules.-After Clark. 



toms' and desmids, circulate in regular, fixed currents, the 

 arrows in the figure indicating the course of the circulating 

 food. The act of circulation is probably assisted by a con- 

 tractile vesicle (or 

 vacuole) usually 

 present. There is 

 besides a distinct 

 organ always pres- 

 ent, the nucleus (see 

 Fig. 11), so that the 

 Amo3ba earns the 

 right to be called 

 an organism. Its 

 food consists of one- 

 celled ulgas, diatoms, 

 desmids, zoospores, 

 and portions of fila- 

 mentous algae, and it 

 possesses the power 

 of discrimination in 



Fig. 11. Amoeba sphcerococcus. A, before division. 



B, the same in its resting stage; a, cyst or cell-wall; ttlklllg its IOOd. The 

 d, body-mass; c, nucleus; b, nncleonis. C, Amoeba . 11,1 



nearly divided. 7>, two young Amoebse, the result of Amoeba lias the pOW- 

 divieion. After Haeckel. , . i 



er of moving in par- 

 ticular directions, stretching a millimetre in length ; it 

 selects appropriate food, and can engulf or swallow, digest 

 and distribute the food thus absorbed to various portions of 



