HOW PLANTS CAME TO DIFFER. 25 



CHAPTER III. 



HOW PLANTS CAME TO DIFFER FROM ONE 

 ANOTHER. 



All plants are not now alike. Some are trees, 

 some herbs; some are roses, some buttercups. 

 Yet we have a certain amount of reason to believe 

 that they are all descended from one and the 

 same original ancestor ; and we shall see by and 

 by that we can often trace the various stages in 

 their long development. They differ immensely. 

 Some of them are more advanced and more com- 

 plex than their neighbours; some are small and 

 low, while others are tall and strong; some, like 

 nettles and grasses, have simple and inconspicu- 

 ous flowers, while others, like lilies and orchids, 

 have beautiful and very complicated blossoms, 

 highly arranged in such ways as to attract and 

 entice particular insects to visit and fertilise them. 

 Again, some have tiny dry fruits, with small round 

 seeds, which fall on the ground unheeded ; while 

 others have brilliant red or yellow berries, or 

 winged or feathery seeds, especially fitted for spe- 

 cial modes of dispersion. In short, there are 

 plants which seem, as it were, very low and un- 

 civilised, while there are others which display, so 

 to speak, all the latest modern inventions and 

 improvements. 



The question is. How did they thus come to 

 differ from one another ? What made them vary 

 in such diverse ways from the primitive pattern ? 



In order to understand the answer which 

 modern science gives to this question, we must 

 first glance briefly at certain early steps in the 



