XXll 



INTRODUCTORY LESSONS. 



54. Cyme. 53. Spike 



to be Perigynous ; or the stamens may grow on the corolla (Fig. 50) as 

 in most gamopetalous flowers, and in Eschscholtzia (Fig. 49). In the 

 Orchis Family the stamens grow on the pistil. 



Irregular Flowers are those in which parts of the same kind are 

 unlike in form or size. 



Inflorescence. The forms of flower-clusters are almost as various 

 as the shapes of the flowers, but they 

 may all be referred to two plans, viz. : 

 Terminal and Axillary. The Raceme 

 (Fig. 52) is a simple form of axillary 

 inflorescence in which the leaves are 

 reduced to bracts. If the flowers are 

 sessile (without pedicels) the raceme 

 becomes a Spike (Fig. 53). If the 

 older flowers are raised on long pedi- 

 cels the flat-topped cluster is called a 

 Corymb (Fig. 55); In an Umbel the 

 pedicels all grow from the end of the 



peduncle (Fig. 56). If these are 

 very short or obsolete a Head is 



formed. A Panicle is a loose com- 

 pound raceme. A Thyrse is a dense 

 panicle. Fig. 54 represents a Cyme, 

 the type of terminal inflorescence. A 

 many-flowered cyme is a Fascicle ; more 

 densely flowered, a Glomerule. Cymes 

 55 and Fascicles resemble Corymbs; but 



56. Umbel. 55. Corymb. -^^ ^^^ former, the central flowers are 



the older, while in the latter, the younger flowers or buds occupy the 

 center. Glomerules differ from heads in the same way. 



The woodland flowers Trillium and Anemone furnish examples of 

 the simplest form of Terminal Inflorescence. Their simple stems bear 

 each one flower at the top. Often flowers seem to be axillary when the 

 plan of inflorescence is terminal. Fig. 57 illustrates a case of this kind- 



