VIII.] THE PROTEUS ANIMALCULE. 373 



Amoeba would. In the earliest condition of the embryo, 

 the whole body is largely composed of such nucleated cells 

 as the colourless corpuscles of the blood; and the colourless 

 corpuscles must be regarded as simply the progeny of such 

 cells, which have not become metamorphosed, and have 

 retained the characteristics of the lowest and most rudi- 

 mentary forms of animal life. 



The Amoeba is an animal, not because of its contractility 

 or power of locomotion, but chiefly because it is devoid 

 of the power of manufacturing protein from bodies of a 

 comparatively simple chemical composition. The Amoeba 

 has to obtain its protein ready made, in which respect 

 it resembles all true animals, and therefore is, like them, 

 in the long run, dependent for its existence upon some 

 form or other of vegetable life . 



Amcebtz multiply by fission in a manner similar to that 

 described for the bell-animalcule; the nucleus first divides, 

 the cell becoming subsequently cleft in two. Occasionally 

 an Amoeba has been seen to engulph another of smaller size 

 than itself; and there is reason to believe that this process, 

 originally thought to have been one of cannibalism, may 

 probably be one of conjugation of dissimilar individuals, 

 for reproduction, such as is seen in the bell-animalcule. 



LABORATORY WORK. 



A. Place a drop of water containing Amcebce on a slide, 

 cover with a cover glass, avoiding pressure, and search 

 over with J inch obj. : having found an Amoeba, ex- 

 amine with a higher power. 



