THE CELL 23 



on from cell to cell, and it also seems that it has . 

 the power of producing all the other elements of 

 the cell. It consists of a number of small bodies 

 which are called chromosomes and in the division 

 of cells of which fuller details will shortly be 

 given these chromosomes are evenly divided be- 

 tween the mother and the daughter cells. 



The nucleus is then the most important part of 

 the cell and the chrom6somes are the essential part 

 of the nucleus. Slightly to anticipate matters 

 which will be made more clear in another chapter, 

 it may here be said that in addition to the two 

 axioms laid down at the commencement of this 

 chapter we are now in a position to accept a third, 

 laid down by Flemming in 1882, Omnis nucleus e 

 nudeo and even a fourth, postulated by Boveri in 

 1903, Omne chromosoma e chromosomate, for we 

 know that as living thing comes from living thing 

 and cell from cell and not otherwise so nucleus is 

 derived from nucleus and chromosome from chro- 

 mosome and also not otherwise. 



But though the nucleus is the essential part of Relation* o 

 the cell and its chromosomes are the most essential ^J ev 

 factor of the whole structure it does not follow nor 

 is it the case that the nucleus or its chromosomes 

 are self-sufficing. This has been proved by direct 

 experiment. It is possible for the skilled manipula- 

 tor to deprive a unicellular organism of its nucleus. 



