ELEMENTS OF STRUCTURAL BOTANY. 



81 



CHAPTER XIII. 



MORPHOLOGY OF FLOWER-LE.WES. THE CALYX. THE CO- 

 ROLLA. THE STAMENS. THE PISTIL. THE FRUIT. 

 THE SEED. GERMINATION. 



119. From an examination of tlie various forms jn-e- 

 sentecl by foliage leaves, we proceed now to tliose of 

 the floral ones, and we shall first consider the chief 

 modifications in the arrawjrment of flowers as a iriiole, 

 to which the term inflorescence is apphed. 



120. It is found that inflorescence proceeds upon two 

 Trell-define/l plans. To understand these, let us recur 

 to our specimens of Shepherd's- Purse and Buttercup. 

 You will remember that, in the former, the peduncle 

 continues to lengthen as long as the summer lasts, and 

 new flowers continue to be produced at the upper 

 end. Observe, however, that every one of the flowers is 

 produced in the axil of a bract, that as the stem lengthens 

 new bracts appear, and that there i.v no flower on the eiid 

 of the stem. You will easily understand then, that 

 the production of flowers in sucli a plant is only 

 limited by the close of the season or by the exhaus- 

 tion of the plant. Such inflorescence is therefore 

 called indefinite, or indeterminate, or axillary. 

 It is sometimes also called centi-ipeial, because if the 

 flowers happen to be in a close cluster, as are the upper 



