26o THE STORY OF PLANT LIFE 



wards. The female flowers consist of two carpels, 

 placed transversely. The ovary is syncarpous, one- 

 celled, stalkless or stalked. There are two short 

 styles ; there are two stigmas, entire or two- to four- 

 lobed. The ovules are numerous. The placentae are 

 parietal. The ovules are ascending, anatropous. The 

 fruit is a capsule, one-celled, opening by loculi, with 

 two valves, which roll back. The seeds are numerous, 

 very small, without endosperm, and provided with a 

 tuft of hairs which conceals them. The embryo is 

 straight. 



The honey is half concealed and abundant. As 

 the plants are usually dioecious, pollination must 

 be effected by outside agency, such as the wind or 

 insects. Many insects visit the Willows in the early 

 months and must effect cross-pollination. The 

 activity of the bees amongst the Sallows and Willows 

 is a feature of early spring. The Willows also are 

 sweet-scented, and the yellow anthers are conspicuous. 

 It is not therefore a matter for surprise that in 

 this genus there are many hybrids. The Willows 

 and Poplars are also adapted to pollination by the 

 wind. They flower before the leaves are produced, 

 as a rule. Pollen is abundant. The seeds are dis- 

 persed by the wind by aid of the silky tufts of hairs, 

 which serve as parachutes. 



The Willows yield useful timber, and Osiers are 

 used in basket manufacture. The Poplars, which are 

 quick-growing trees, are largely planted for ornamental 

 purposes. 



