CHAPTER XI 
THE INFLORESCENCE 
INFLORESCENCE OF ANTHOTAXY.—The terms Inflorescence 
and Anthotaxy are applied to the arrangement of the flowers and 
their position on the stem, both of which are governed by the 
same law which determines the arrangement of leaves. 
Indeterminate, racemose, ascending, or centripetal inflorescence is 
that form in which the terminal bud of the flower cluster con- 
tinues to develop and increase the length of the stem indefinitely. 
As the stem elongates new flower buds arise behind the terminal 
bud in the axils of reduced foliage leaves called bracts, so that the 
oldest bud is at the base of the flower cluster and the youngest one 
is nearest the apex. Example: Digitalis. 
Determinate, cymose, descending, or centrifugal inflorescence is 
that form in which the opening of the terminal bud as a flower 
determines or completes the growth of the stem of the flower 
cluster. Example: Ricinus communis. 
Mixed inflorescence is a combination of the other two forms. 
Example: Horse Chestnut. 
The flower stalk is known as the peduncle. Its prolongation 
beyond the point where flowers or branches begin to appear is 
called the rachis, or axis of the inflorescence. 
The flower stalk of a single flower of an inflorescence is called a 
pedicel. When borne without such support the flower is sessile. 
_ A peduncle rising from the ground is called a scape, previously 
mentioned under the subject of stems. 
The modified leaves found on the peduncle or its extension, 
the rachis, are termed bracts. These vary much the same as leaf 
forms, are described in a similar manner, and may be either green 
or colored. When collected in a whorl at the base of the 
peduncle they form an involucre, the parts of which are sometimes 
imbricated or overlapping, like shingles. This is generally green, 
but sometimes petaloid, as in the Dogwoods. The modified 
leaves found on pedicels are called bracteolar leaves or bracteoles. 
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