CHAP. 11. INFLORESCENCE. 129 



5. Of the Inflorescence. 



Infiorescence is a term contrived to express generally the 

 arrangement of flowers upon a branch or stem. The part 

 which immediately bears the flowers is called the pedunculus 

 or peduncle, and is to be distinguished from any portion of a 

 branch by not producing perfect leaves ; those which are 

 found upon it called brads being much reduced in size and 

 figure from what are borne by the rest of the plant. 



The term peduncle, although it may be understood to apply 

 to all the parts of the inflorescence that bear the flowers, is 

 only made use of pi'actically, to denote the immediate support 

 of a single solitary flower, and is therefore confined to that 

 part of the inflorescence which first proceeds from the stem. 

 If it is divided, its principal divisions are called branches; and 

 its ultimate ramifications, which bear the flowers, are named 

 pedicels. There are also other names which are applied to its 

 modifications. 



In plants which are destitute of stem, it often rises above 

 the ground, supporting the flowers on its apex, as in the 

 Cowslip. Such a peduncle is named a scape [hampe, Fr.). 

 Some botanists distinguish from the scape the pedunculus radi- 

 calism confining the former term to the pedmicle which arises 

 from the central bud of the plant, as in the Hyacinth ; and 

 applying the latter to a pedmicle proceeding from a lateral 

 bud, as in Plantago media. 



When a peduncle proceeds in a nearly right line from the 

 base to the apex of the inflorescence, it is called the rachis, or 

 the axis of the inflorescence. This latter term was used by 

 Palisot de Beauvois to express the rachis of Grasses, and is 

 perhaps the better term of the two, especially as the term 

 rachis is applied by Willdenow and others, without much 

 necessity it must be confessed, to the petiole and midril of 

 Ferns. In the spikelets of Grasses the rachis has an unusual, 

 toothed, flexuose appeai'ance, and has received the name of 

 scohina from Dumortier. If it is reduced to a mere bristle, 

 as in some of the single-flowered spikelets, the same writer then 

 distinouishes it by the name of acicula. 



When the part which bears the flowers is repressed in its 



K 



