DKECIOUS FLOWERS. 



55 



fcheir insertion, and observe- that they spring from the 

 axil of a minute bract (Fig. 70). These bracts are the 

 scales of the catkin. There is no appearance of either 

 calyx or corolla, and the flowers are therefore said to be 

 achlamydeous, that is, without a covering. Now 

 look at the fertile catkin. Each pistil will, like 

 the stamens, be found to spring from the axil of 

 |/ a scale (Fig. 71). The stigma is two-lobed, and, 

 on carefully opening the ovary, you observe that 

 though there is but one cell yet there are two 

 rows of seeds. We therefore infer that the pistil 

 Fig. 71. consists of two carpels. The pistillate flowers, 

 like the staminate, are achlamydeous. In dioecious plants 

 HEABT-LEAVED WILLOW. 



the process of fertilization is assisted by insects, especially 

 when the flowers are showy or odoriferous and nectar- 

 Fig. 71. Single pistillate flower of Willow. 



