FORM AND LIFE. 523 



other point, and the viscous drop, changing shape continually, 

 seems to flow along slowly. If it meets any vegetable matter, it 

 envelops it, and the stuff suffers a real digestion. The residue is 

 cast out, as it was absorbed, by any point of the surface. We 

 call these beings amo&bas. They are capable of multiplication 

 by division, and every part of them is susceptible of being indif- 

 ferently surface or inside, the drawing part or the part drawn, 

 mobile all at once. For the amoeba can choose its direction and 

 find more light or more darkness according to what we may call 

 its aspirations, since it acts, definitively, as a living being. 



If we open a tan vat in the spring, we shall discover here and 

 there irregular golden-yellow filaments, soft and slimy. We ob- 

 serve them changing their place and flowing like the amoDbas. 

 They appear to be seeking one another in the mass of tan, for in 

 the summer, after a shower, they may be seen to join, then rise in 

 the shape of a kind of yellow cake, large and thick as the two 

 hands ; jbhe botanists call them rinjxomyceta, or the slimy fungus. 

 Detach a part of this mass, put it on a potsherd, and it will, like 

 the amoeba, extend branchy expansions, pass itself upon them, 

 stretch out and return upon itself in changing lumps, to be suc- 

 ceeded soon by new stretchings. 



We see in these, beings without form, without organs, com- 

 posed solely of an opaque substance, and highly colored in the 

 myxomycetes, but transparent in the amoeba, a little denser than 

 water, with which it does not mix, a substance that moves and 

 feels that is, that shares with us the higher attributes of life. 

 The discovery of the amoebas was at first merely a curiosity till 

 Dujardin and Hugo Mohl, almost at the same time, called atten- 

 tion to a substance entering into the composition of infusoria 

 and the cells of plants that had all the characteristics of the sub- 

 stance of the amoebas. Dujardin called it sarcode ; Hugo Mohl, 

 X)rotoplasma, and that name prevailed. The term, imposed as the 

 name of one of the constituent parts of the vegetable cell, has had 

 the singular fortune to become almost synonymous with matter 

 living or that has lived. 



This amorphous substance is the basis of the organism. In 

 plants, it is what in some way builds up every cell, as the worm 

 and the mollusk produce the shell and the tube that protect them, 

 or as the caterpillar envelops itself with the cocoon which it draws 

 out from its glands. So the protoplasm molds around itself the 

 walls of the cell in which it is inclosed. But it is always the prime 

 living part, and when it disappears the cellular wall becomes only 

 an inert body. In animals, likewise, the Qgg, or at least its essen- 

 tial part, the vitellus, shows in its almost universal spherical form 

 the protoplasm shaped at first only by the laws of attraction and 

 resistance common to all "itiatter. But when the egg takes life, the 



