SOME PLANT BIOGRAPHIES. 183 



all life is really, in Mr. Herbert Spencer's famous 

 phrase, "adaptation to the environment;" and 

 therefore we can only understand and discover 

 the use and meaning of each part or organ by 

 watching the plant in its own home, and among 

 the general conditions by which it and its ances- 

 tors have always been limited. It would be im- 

 possible, for example, to see the use of the thick 

 outer covering of the coconut (from which coco- 

 nut matting is manufactured) if we did not know 

 that the coconut palm grows naturally by the sea- 

 shore in tropical islands, and frequently drops its 

 fruits into the water beneath it. The nuts are 

 thus carried by the waves and currents from islet 

 to islet ; and the coconut palm, which is a deni- 

 zen of sea-sand, owes to this curious method of 

 water-carriage its wide dispersion among the 

 coral-reefs of the Pacific. But a plant that is so 

 dispersed must needs make provision against 

 wetting, bruising, and sinking in the sea; and 

 since only those coconuts would get dispersed 

 over wide spaces of water which happened to 

 possess a good coating of fibre, the existing plant 

 has come to produce the existing nut as w^e know 

 it — richly stored with food for the young palm 

 while it makes its first steps among the barren 

 rocks and sand-banks, and well provided by its 

 shaggy outer coat against the dangers of the sea, 

 the reefs, and the breakers. Similarly, we could 

 never understand the cactus except as a native 

 of the dry plains of Mexico. Or again, there is 

 an orchid in Madagascar with a spur containing 

 honey at a depth of eighteen inches. Now, no 

 European insect could possibly reach so deep a 

 deposit; but a Madagascar moth has a gigantic 

 proboscis, exactly fitted for sucking the nectary 



