CORYMBS 



121 



cal cases) have only one sex. Ex- 

 amples are the "pussies" of willows 

 (Fig. 229) and flower-clusters of 

 oaks (Fig. 228), hickories, poplars 

 and walnut (Fig. 190). 



253. When a loose, elongated 

 corymbose flower-cluster branches, 

 or is compound, it is called a pan- 

 icle. Because of the earlier growth 

 of the lower branches, the panicle 

 is usually broadest at the base or 

 conical in outline. The flower- 

 cluster of the oat is an example. 

 (Fig. 191.) True panicles are not 

 common. 



254. When an indeterminate 

 flower-cluster is short, so that the 



top is con- 

 vex or flat, 

 it is a 

 corymb. 

 (Fig. 192.) 

 The outer- 

 most flowers open first. Fig. 193 

 shows many corymbs of the bridal 

 wreath, one of the spireas. 



255. When the branches of an 

 indeterminate cluster arise from a 

 common point, like the frame of 

 an umbrella, the cluster is an umbel. 

 (Fig. 194.) Typical umbels occur 

 in carrot, parsnip, parsley and other 

 plants of the parsley family: the 



190 Catkins of black walnut, f y - k th UmbellifeWB. 



at b. Pistillate flowers at a. J 



Paragraph 284. or umbel - bearing family. In the 



189. Terminal heads of the white- 

 weed (in some places erro- 

 neously called ox-eye daisy). 



