THE CELL 21 



be one of enormous complexity. Again, however, 

 it must be insisted that we know not what may 

 be the actual state of affairs in living protoplasm, 

 nor do we even know that the composition of the 

 protoplasm in one part of a cell may not differ 

 from that in another part, whilst that cell is alive. 

 " Protoplasm," says Wallace, 1 " is so complex chem- 

 ically as to defy exact analysis, being an elaborate 

 structure of atoms built up into a molecule in which 

 each atom must occupy its true place, like every 

 carved stone in a Gothic Cathedral." Pflliger, too, 

 a very distinguished German physiologist, tells us 

 that living proteid or protoplasm is a huge mole- 

 cule, undergoing constant, never-ending formation 

 and decomposition, and gives us an illuminating 

 view of its characters when he says that it probably 

 behaves towards the usual chemical molecules as 

 the sun behaves to small meteors. 



Much attention has been devoted to the solu- 

 tion of the question of the structure of protoplasm, 

 but so far, if must be admitted, without any 

 definite results. 



The cell is generally included by a wall, and if Parts of ceil 

 the unscientific person wishes to obtain a rough 

 idea of what it is like he may imagine a child's toy 

 air-balloon filled with unboiled white of egg. In 

 the centre of this white of egg let him suppose that 

 1 Mans Place in the Universe, p. 199. 



