154 THE BOOK OF NATURE STUDY 



such a fully opened specimen (Fig. 74). The perianth will be 

 found to consist of six small brown pointed leaves, which form two 

 series of three, the inner whorl alternating with the outer whorl. 

 The perianth leaves are very unlike the delicate coloured petals 

 of most other flowers. They are dry and scale-like, with a, thicker 

 brown midrib and a thin greenish or brown margin. While they 

 protect the parts within in the bud, they do not, even when fully 

 expanded, render the flower conspicuous, as do the petals of many 

 equally small flowers. 



Within the perianth come six stamens, also in two whorls of 

 three. Each stamen has a short stalk, which continues into a 

 relatively large anther. In the unopened anthers the four pollen- 

 sacs can be distinguished as four 

 ridges, but on the opening of the 

 anther the loose powdery pollen is 

 exposed. In the centre of the 

 flower is the pistil, consisting of the 

 small green triangular ovary, a 

 slender style, and the three long 

 branches of the stigma. The pistil 

 is composed of three carpels, as is 



FIG. 74-Fiower of the Field Wood- indicated by the number of stig- 

 rush fully opened. (After Baiiion.) matic lobes, which are by now 



withered and no longer capable of 



receiving pollen. The ovary contains three ovules in its single 

 cavity, and at this stage has commenced to develop into the 

 fruit. 



The features of this flower can only be understood in the light 

 of the method of pollination. The flowers are inconspicuous and 

 secrete no nectar. They thus offer no inducements to insects to 

 visit them. They are, in fact, pollinated by the help of the wind, 

 and not by insects, and all the characters in which they differ 

 from brightly coloured and conspicuous flowers fit them for this. 

 The pollen, in contrast to that of most of the other plants described 

 here, is loose and powdery, and the stamens are freely exposed 

 in the open flower. If on a fine warm day one of the inflorescences 

 be gently tapped or shaken, a cloud of dusty pollen will be found 

 to escape into the air. Evidently thousands of pollen grains will 



