176 THE HUMAN SIDE OF PLANTS 



stalks entirely hidden under the water. The Ital- 

 ian eel-grass (Vallisneria spiralis) uses this unique 

 method of fertilisation. The female flowers grow 

 on long, spirally twisted stalks, and each flower is 

 enclosed in a small bladder. The male flowers grow 

 in bunches, and each entire bunch is covered with 

 a thin skin-like sheath. The female flower has con- 

 tinued to reach up her head until the flowers rest 

 on the surface of the water; while the male is tied 

 down below by a short stalk. 



Now the miracle happens! The gallant wooer 

 deliberately breaks loose from his underwater posi- 

 tion, and arises to the top where his lady-love is 

 peacefully floating! The male flower bursts open 

 his sepals and forms a tiny raft, and, by means of 

 this raft, he is enabled to float around until some 

 kind wind or wave brings him in contact with his 

 love. Some of the pollen from the male adheres to 

 the female flower; she drops to the bottom of the 

 water, and there remains while the seeds are being 

 developed. 



There are many flowers that cater neither to 

 birds, insects, nor water, but look only to the wind 

 for fertilisation. These wind-fertilised flowers 

 usually are not conspicuous ; for example, there are 

 many of the grasses, to say nothing of the large 

 trees. Exceptions are found in quack-grass, 



