THE FLOWER 



143 



Diagram of a 

 simple cyme 

 in which the 

 axis length- 

 ens, so as to 

 take the form 

 of a raceme. 



306. Wherever there are bracts or leaves, buds may be produced 

 from their axils and appear as flowers. Figure 252 represents the case 

 where the branches, hb, of Fig. 251, each with a pair of small leaves 

 or bracts about their middle, have branched again, and produced the 

 branchlets and flowers, cc, on each side. It is the continued repetition 

 of this which forms the full or compound cyme, 



such as that of the Hobblebush, Dogwood, and 

 Hydrangea. 



307. A Fascicle (meaning a bundle), like that 

 of the Sweet William and Lychnis of the gardens, 

 is only a cyme with the flowers much crowded 

 together. 



308. A Glomerule is a cyme still more com- 

 pacted, so as to imitate a head. It may be known 

 from a true head by the flowers not expanding 

 centripetally ; that is, not from the circumference ^ 

 toward the center. 



309. Scorpioid or Helicoid Cymes, of various 

 sorts, are forms of determinate inflorescence (often 

 puzzling to the student) in which one-half of the 

 ramification fails to appear. So that they may 

 be called incomplete cymes. The commoner forms 



may be understood by comparing a complete cyme, like that of 

 Fig. 252, with Fig. 254, the diagram of a cyme of an opposite-leaved 



plant, having a series of terminal flowers 

 and the axis continued by the development 

 of a branch in the axil of only one of the 

 leaves at each node. The dotted lines on 

 the left indicate the place of the wanting 

 ^_^^, ^^ branches, which if present would convert 



]/|[^^ ^ \,^<\ this scorpioid cyme into the complete one 



of Fig. 252. Figiu'e 254 a is a diagram 

 of similar inflorescence with alternate 

 leaves. An axis made up in this way of a 

 succession of branches is termed a sympodium. 



310. Mixed Inflorescence is that in which the two plans are mixed 

 or combined in compound clusters. A mixed panicle is one in which, 

 while the primary ramification is of the indeterminate order, the 

 secondary or ultimate is w4iollyor partly of the determinate order. A 

 contracted or elongated inflorescence of this sort is called a Thyrsus. 

 Lilac and Horse-chestnut afford common examples of mixed inflores- 

 cence of this ^ort. When loose and open such flower clusters are called 

 by the general name of panicles. The heads of Composit?e are cen- 

 tripetal ; but the branches or peduncles wdiich bear the heads are 

 usually of centrifugal order. 



•irA a 



