How Plants Perpetuate Their Kinds 



287 



or, if one pleases, it is fertilization without sex. In the next place 

 there are other and more highly organized seaweeds in which the 

 reproductive cells given off into the water are of two different 

 kinds, although produced by the same parent plant. One kind is 

 very much larger, round, and without arrangements for locomo- 



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Fig. 101. — The appearance and behavior of the chromosomes during the division of a 

 typical plant cell, as seen, somewhat generalized, in a series of optical sections highly 

 magnified. A fuller description of the division of the chromosomes is given on page 

 284 of this book. (Copied from Strasburger's Textbook.) 



tion, while the other is much smaller, of elongated shape and pro- 

 vided with good swimming organs (figure 103). All of the move- 

 ment necessary to bring the two cells together in fertilization is 

 made by the active smaller cell, which, guided no doubt by some 

 chemical secretion, swims to the passive larger one and fuses 

 therewith; the two nuclei then unite and from this fertilized cell 



