28 PHENOMENA OF PLANT-LIFE. 



that conduces in any way to the stability and decora- 

 tion of the general fabric. These tiny seeds that float 

 in the air, have for their special function the starting 

 of life in places where previously there was none. 

 The moment that any surface previously bare, becomes 

 moistened with rain or dew, they settle upon it as bees 

 do upon flowers. If not burned up by the sun, in a 

 little while there is a thin green film of vegetation, 

 and by and by is seen a colony of mosses. Hence, 

 upon the old cottage roof, especially if it be of thatch, 

 that sweet and rich variety of tender leaf and blossom. 

 Every spray is the growth of a seed wafted thither by 

 the wind. It almost seems as if the atmosphere held 

 plants in solution, and deposited them as a chemical 

 fluid deposits crystals. 



But let us inquire what a seed is composed of; 

 what is the constitution, or at least, the aspect of 

 those wonderful parts which a little rain and a little 

 sunshine can tempt into expansion, and by and by 

 develop into a flower or tree. In its most perfect 

 state, a seed consists of several distinct elements. 

 Outside of all is the protecting skin, by botanists 

 called the " testa ; " when this is removed, the interior 

 is found to consist either of two solid white halves, 

 usually flattened upon their inner surfaces, as in a pea 

 or bean, or it consists of a quantity of white and fari- 

 naceous matter, well represented in the flower of a 

 grain of wheat. Look a little further, and if the seed 



