HOW PLANTS BEGAN TO BE. 25 



then the two halves continue to exist inde- 

 pendently. No two distinct plants or parts of 

 plants are concerned in producing each new 

 individual. But the higher plants, like the 

 higher animals, are male and female. In such 

 cases two distinct individuals combine to form 

 a new one. They are its father and mother, so 

 to speak, and the young one is their offspring. 

 A little grain of pollen produced by the male 

 plant unites with a little ovule or seedlet pro- 

 duced by the female ; and from the union of the 

 two springs a fresh young plant, deriving its 

 peculiarities about equally from each of them. 

 How and why this great change in the mode 

 of reproduction takes place is another of the 

 questions we must discuss hereafter; I will 

 only anticipate now the result of this discussion 

 by saying briefly beforehand that plants gain in 

 this way, because greater variety is secured in 

 the offspring, and because the weak points of 

 one parent are likely to be reinforced and made 

 good by the other. 



Let us sum up our conclusions in this pre- 

 liminary chapter : — 



Plants are an older type of life than animals. 

 They are the first and most original form of 

 living beings, and without them no life of any 

 sort would be possible. All living matter is 

 manufactured by plants out of material found 

 floating in the air, under the influence of sun- 

 light. How plants first came into existence we 

 do not yet know ; but we may suspect that they 

 greW; in very simple and small forms, at a 



