CHAPTER LXL 



DICOTYLEDONS. 



Topic V: Dicotyledons with distinct petals, flowers 

 in catkins, or aments; often degenerate. 



ORDER SALICALES. 



1158. Lesson VI. The willow family (Salicaceae). The wil- 

 lows represent a very interesting group of plants in which the 

 flowers are greatly reduced. The flowers are crowded on a 

 more or less elongated axis forming a catkin, or ament. The 

 ament is characteristic of several other families also. The 

 willows are dioecious, the male and female catkins being borne 

 on different plants. The catkins appear like great masses of 

 either stamens or pistils. But if we dissect off several of the 

 flowers from the axis, we find that there are many flowers, each 

 one subtended by a small bract. In the male or "sterile" cat- 

 kins the flower consists of two to eight stamens, while in the 

 female or "fertile" catkins the flower consists of a single pistil. 

 The poplars and willows make up the willow family. 



SUGGESTIONS FOR STUDY OF THE WILLOW. 



1159. The willow (Salix discolor). 



The leafy shoot. Determine the arrangement of the leaves of the willow; 

 sketch a leaf showing its form, the character of the margin and of the vena- 

 tion. If different willows are at hand, compare the color of the twigs, as 

 well as the character of the twigs as to brittleness or litheness. 



The inflorescence. What is the kind of inflorescence ? Are both kinds 

 of flowers borne on the same ament (catkin) or on different aments? 



The staminate catkins. Determine what constitutes a flower by dis- 

 secting some of them off from the axis of the catkin. What parts of the 



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