124 



WEEDS OF THE FARM AND GARDEN 



tendril. These tendrils are modified leaves, while those 

 of the grape are modified stems. , 



Flowers. Flowers are for the purpose of producing 

 seed and are merely altered branches; the parts of flow- 

 ers are therefore altered leaves. The manner in which 

 flowers are borne upon the stem 

 is important in enabling one to 

 distinguish different plants. The 

 manner in which the flowers are 

 borne is called the inflorescence, 

 and there are two types : the de- 

 terminate, where the terminal 

 bud opens first; and the indeter- 

 minate, where the flowers develop 

 from below. The more important 

 types of indeterminate inflores- 

 cence are the following: 



Raceme, a simple flower cluster 

 in which the flowers are attached 

 to a little stalk called a pedicel, 

 and are arranged along a common 

 axis. Ex- 

 amples are : 

 The cur- 

 rant, shep- 

 herd's 



purse, and lily of the valley. A 

 corymb is much like a raceme, ex- 

 cept that the flowers are more or 

 less level at the top and the ped- 

 icels are of different lengths. In 

 an umbel the flower cluster is 

 much the same as in a corymb, 

 but the stalks are all of the same 



length; in other words, the flowers p . g ^ Inflorescence> 

 come from the end of the stalk. Cymose cluster of pink. 



Fig. 58. Inflorescence. 

 Catkin of birch: 2, stamin- 

 ate flowers; 3, pistillate 

 flowers. 



