CHAPTER XXXVII 

 THE PERPETUATION OF LIFE 



All organisms have the property of producing other or- 

 ganisms similar to themselves and thus continuing their 

 race. In the simplest forms of life new individuals com- 

 monly arise by the division or fission of the parent form. 

 An Amoeba or Paramcecium, as we have seen, simply con- 

 stricts in two and the new individuals soon regain their 



FIG. 225. Pandorina morum. A, gametes formed by repeated divi- 

 sions of the cells of the colony. These gametes meet and fuse and 

 finally lose their flagella and become converted into a spherical encysted 

 zygote, 2. 



normal size and shape. Other organisms reproduce by 

 budding, such as most hydroids, sponges, several kinds of 

 worms and many other primitive animals. In some of 

 the Protozoa the body divides up into a number of bodies 

 called spores which scatter and develop new individuals. 

 In organisms except the very simplest, such as the bac- 

 teria, the process of reproduction is commonly associated 



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