REPRODUCTION AND EARLY DEVELOPMENT. 99 



to the same sort of youth which the parent had at its 

 beginning. The student must keep both of these facts 

 in mind in all that is to be said of reproduction. 



105. The Formation of New Individuals. This is 

 always done by some sort of division of the old individual. 

 The parts may be equal or unequal ; they may be just two 

 or they may be numerous, but it is always a division at the 

 expense of the parent, or original individual. It is just 

 the opposite of the nutritive process. Nutrition builds 

 Ji 



FIG. 18. Diagram illustrating the reproduction of organisms by budding. A, 

 yeast cells, b, the bud or daughter cell; m, the mother cell. B, Chlamydomyxa, a lowly 

 protozoan, c.w., cell wall; n, nuclear matter. 



Questions on the Figure. How does reproduction by budding 

 differ from ordinary cell division? If the buds remain attached to 

 the mother what is the result? If they become separate what 

 results? 



up, or increases the mass of the old self. Reproduction 

 separates a new individual at the expense of the old self. 



Practically all cells have, orginally, this power of divi- 

 sion or reproduction. We call it cell division. Some 

 figures of its stages will be seen in Fig. 15. In this case 

 the daughter cells are equal and there is no parent x:ell left. 



Often, however, the daughter cell is not of the same 

 size as the mother cell. It begins small and grows to its 

 mature size (Fig. 18). This is known as budding. 



