BO TA NIC A L TERM S. 



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The Raceme, Umbel, and Corymb may be compound, 

 as shown in Figs. lOo (compound llaceme) and 104 (com- 

 pound Unibcl). 



(g) A Catkin ; when the flowers (usually imperfect) 

 arise from scale-like bracts along a slender axis. The 

 Catkin is thus a special kind of spike (Fig. 105). 



(h) A Spadix : when the flowers (often imperfect) are 

 arranged in a spike-like cluster on a fleshy axis, as in 

 Indian-Turnip (Fi^rs. 106 and 107). 



The Spadix is usually surrounded by a large showy 

 bract called a spathe (Fig. 108). 



Mixed : when axillai-y and terminal forms are combined. 

 For example, in many Composites the inflorescence is 

 terminal or cymose as to the heads thevisslves, while each 

 head separately is always axillary or lateral as to the 

 developniont of the florets of which it is made up. The 

 chief varieties of mixed inflorescence are 



(a) The Thyrse : a cluster like that of Lilac, in which 

 the primarj' branches are lateral, and the secondary 

 cymose. 



(b) Vcvticillaster : a cluster like that of Catnip and 

 Mint flowers generally, where two dense cymes form in 

 the ;vxils of opposite leaves, giving the appearance of a 

 whorl. 



In connection with inflorescence the following terms 

 should be noticed : 



Pedvncle : the flower-stalk, or in the case of clusters 

 the stalk supporting the whole cluster. 



Pedicel : the separate stalk of each flower in a cluster. 



Scape ; a leafless flower-stalk rising from the ground 

 or near it, as in Tulip and Dandelion. 



Bract : a foliage-leaf, differing from the ordinary leaves 

 of the plant in size, shape or colour, anil found iiTidcr 

 the flower or flower-cluster. 



Bractlet : a secondarj- bract, as seen on the i)edicels in 

 Fig. 103. 



Involucre: a circle of bracts, such as the outer leaves 

 of Composite flowers like Dandelion, etc. (Fiir. lOPl 



Involucel : a .secondarj' or minor involucre or circle of 

 bractlets, such as is commonl3- found under the small 



clusters of a compound umbel (Fig. 104). 



Flpr. 104. 



Fig. 103. 



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Fig. lOa. 



