38 



PHARMACEUTICAL BOTANY 



The flower stalk is known as the peduncle, and its prolongation 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 men- 

 tioned under the subject of stems. 



The modified leaves found on peduncles 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 



Fig. 28. — Types of racemose inflorescence;^, A raceme. B, Aspike. C, Acatkin. 

 D, A corymb. E, An umbel. The flowers are represented by circles; the age of the 

 flower is indicated by the size. (From Hamaker.) 



green, but sometimes petaloid, as in the Dogwood. The modified 

 leaves found on pedicels are called bracteolar leaves. 



The Spathe is a large bract enveloping the inflorescence and often 

 colored, as in the Calla, or membranous, as in the Daffodil. 



In the indeterminate or axillary anthotaxy, either flowers are pro- 

 duced from base to apex, those blossoming first which are lowest down 

 on the rachis or from margin to centre. The principal forms of this 

 type are: A solitary indeterminate is one in which the flowers occur 

 singly in the axils of the leaves. 



Raceme, or simple flower-cluster in which the flowers on pedicels of 

 nearly equal length are arranged along an axis. Ex.: Convallaria, 

 Cimicifuga, and Currant. 



