INFLORESCENCE. 



81 



resemble the petals of one 

 corolla, and the involucre, 

 formed of many imbricated 

 scales, resembles a calyx. This 

 head is often called a com- 

 found fioioer. The outer flo- 

 rets are the florets of the ray^ 

 the interior are the florets of 

 the dish. See all this illus- 

 trated in Figs. 245-250. 



157. The forms of inflo- 

 rescence heretofore described 

 result from axillary buds ; 

 but the three following come 

 from terminal buds. Cyme is 

 the general name given to all 

 the forms of terminal inflores- 

 cence. You may recognize 

 them by the order in which 

 the flowers open. Thus, in 

 the cyme, the terminal and central flowers open flrst, but in 

 the forms before mentioned, the lower and outer flowers first. 



158. When the cyme is spreading and level-topped, we call 

 it a cymous corymh^ as in the common Elder ; and when not 

 level topped, it may become a cymous panicle^ as in Chick- 

 weed (Fig. 251), Spergula, and Stafi*-tree (Fig. 234). 



159. The scorpoid cyme is a very remarkable form of in- 



157. Are the forms hitherto described terminal or axillary ? Please define 

 ihe cyme. 



158. Cymose corymb ; Cymose panicle. 



159. What is a scorpoid cyme? Name and describe the inflorescence of 

 Baucli Pink ; the inflorescence of Catmint. 



4* 



Fig. 245. Head of Blue Milkweed 

 {Mulgedlum) ; all its florets are ligulate. 

 Fig. 246. A view of one of them remain- 

 ing on the receptacle. Fig. 247. A fruit 

 crowned with its pappus. 



Fig. 248. Heads of Ironweed {Verno- 

 nia) ; all its florets are tubular. Fig. 249. 

 One of them remaining on the receptacle. 

 Fig. 250. Fruit. 



