LESSON 11.] DKTKUMINATE INFLORIlSCKNCE- 



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210. A Calkin or Amcill id the nanic given to the scaly sort of spiko 

 of the Birch and Alder, the Willow and Poplar, and one sort of 

 flower-chisters of the Oak, Hickory, and the like ; — on which ac- 

 count these are called Amentaceous trees. 



211. Sometimes these forms of flower-clusters become compound. 

 For example, the stalks which, in the simple umljel such ,ns hjis 

 been described (Fig. 150), are the pedicels of single flowers, may 

 themselves branch in the same way at the top, and so each become 

 the support of a smaller umbel; as is the case in the Parsnip, Cara- 

 way, and almost the whole of the great family of what are called 

 UinbeHlferous (i. e. umbel-bearing) plants. Here the whole is 

 termed a compound umbel; and the smaller or partial umbels take 

 the name in Kiiglish of umbeUets. The general involucre, at the 

 base of the main umbel, keeps that name ; while that at the base 

 of each umbellet is termed a, partial involucre or an involucel. 



212. So a corymb (Fig. 158) with jts separate stalks branching 

 again, and bearing smaller clusters of the same 

 sort, is a compound corymb; of which the Moun- 

 tain Ash is a good example. A raceme where 

 what would be the pedicels of single flowers 

 become stalks, along whic;h flowers are disposed 

 on their own jiedicels, forms a compound raceme, 

 as in the Goat's-beard and the False Spikenard. 

 But when what would liave been a raceme or a 

 corymb branches irregularly into an oi)en and 

 more or less compound flower-cUister, we have 

 what is called 



21.]. A Pailirlc (Fig. 1G3); as in the Oat and 

 in most eoiuinon Gnisses. Such a raceme as that 

 of the diagram. Fig. 15G, would be changed into 

 a jianicle like Fig. 1 ().'), by the production of a 

 flower from the axil of each of the bractlets b. 



211. A Thyrsus is a compact panicle of a pyram- 

 idal or oblong shape; such as a bunch of grapes, 

 or the cluster of the Lilac or Ilorsechestnut. 

 215. DftmnillUtC InfloresCPUrc is that in whuh the flowers arc from . 

 teriniiiiil lunl-. The simple.-t cjuse is where a stem bears a soli- 

 tary, terminal llowcr, as in Fig. 1G3*. This stoi>s the growth of 



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FlU. 1G3. .\ rai:icl« 



S&F— 5 



