THE WIND AS CARRIER. 133 



the most useful food-plants of man, such as wheat, 

 rice, barley, Indian corn, and millet. 



Grasses are for the most part plants of the 

 open wind-swept plains, and they seem naturally 

 to take therefore to wind-fertilisation. Their 

 flowers are generally small, clustered into light 

 spikes or waving panicles, and hung out freely to 

 the breeze on slender and very movable stems, 

 so as to yield their pollen to every breath of air 

 that passes. Moreover, the plants as a whole are 

 slender and waving, so that they bend before the 

 breeze in the mass, as one often sees in a meadow 

 or cornfield. Thus the grasses are almost the 

 pure type of wind-fertilised plants; certainly 

 they have carried further than any other race 

 the devices which render wind-fertilisation more 

 certain. 



On this account they are so complicated and 

 varied that I will not attempt to describe them in 

 detail. I will only say that grasses are descend- 

 ants of the threefold flowers, and in all proba- 

 bility degenerate lilies. Their individual blos- 

 soms usually consist of a very degraded calyx 

 (d and e] of two sepals (one of which represents a 

 pair that have coalesced, Fig. 30). Inside these 

 sepals come two very minute white petals (c and 

 c] ; the third has disappeared, owing to pressure 

 one-sidedly. The petals can scarcely be seen 

 without the aid of a pocket-lens. Next comes 

 three stamens (b\ the only part of the flower 

 which still preserves the original threefold ar- 

 rangement. Last of all we get the ovary (#), of 

 one carpel, one seeded, but with two feathery 

 stigmas, which were once three. In a very few 

 large grasses, such as the bamboos, the threefold 

 arrangement is much more conspicuous. As a 



