452 



HUTCHINSON'S POPULAR BOTANY 



flowers are borne on long stalks (fig. 517, ), each of which, whilst the 

 stigmas are maturing, is enveloped in a kind of bladder. The staminal 

 flowers are similarly invested, but they grow in thick clusters, and one sheaf 

 suffices for all the individuals of a cluster. Each of these male inflorescences 

 is borne on a short rachis (fig. 517, 6, c), which remains short to the end of 

 the chapter ; but at a certain stage the pedicels of the female flowers 

 lengthen to an extraordinary extent, and presently reach the surface of the 

 water. The floral sheaths in the plants of both sexes meanwhile fall apart, 

 and everything betokens readiness for nuptial celebrations. 



But now an interesting problem arises. While the female flowers, held 

 by their thread-like pedicels, are floating restfully on the bosom of the 

 water, the male flowers are anchored far down' below by their diminutive 

 stalks to the short axes. How are the sexes to bej-brought together? The 



problem is solved in 

 a very wonderful, 

 and, at the same time, 

 a very simple man- 

 ner. The submerged 

 male flower-buds de- 

 tach themselves 

 spontaneously from 

 their axes, and, being 

 lighter than the 

 water, ascend to the 

 surface. Here they 

 drift about for a 

 while ; then open, 

 and, twisting back 

 their three sepals in 

 an ingenious man- 

 ner, so as to make a 

 float, bring into view 

 the two perfect sta- 

 mens, which now 

 stand well out of the 

 water like a pair of 

 snail's horns. These 

 miniature floats, as 

 Kerner beautifully 

 remarks, "are blown 

 hither and thither by 

 the wind, and accu- 

 mulate in the neigh- 

 bourhood of fixed 



IB. Step. 



FIG. 556. OAK (Quercus robur). 



These are the male flowers in long, loose catkins. The female flowers borne by the 

 same tree are like little buds, and not so noticeable. 



