ESSENTIAL ORGANS — THE PISTIL. 235 



place is occupied by glandular bodies forming the disk (fig. 346, 

 2, a). In Gesneracese and Cruciferse the disk consists of tooth-like 

 scales at the base of the stamens (fig. 377, t). TJa.e parts forming the 

 disk sometimes unite and form a glandular ring, as in the Orange ; or 

 a dark-red lamina covering the pistil, as in Paeonia Moutan (fig. 404, 

 d) ; or a 'waxy lining of the calyx tube or hollow receptacle, as in the 

 Eose (fig. 29.4, ct) ; or a swelling at the top of the ovary, as in Um- 

 belliferse, in which the disk is said to be epigynous. The enlarged 

 torus covering the ovary in Nymphsea and Nelumbium may be re- 

 garded as a form of disk. 



The Pistil. — The pistil occupies the centre or axis of the flower, 

 and is surrounded by the stamens and floral envelopes, when these are 

 present. It constitutes the innermost whorl, and is the female organ 

 of the plant, which after flowering is changed into the fruit, and con- 

 tains the seeds. It sometimes receives the name of gynxcium (yuH), 

 pistil, olxiov, habitation). It consists essentially of two parts, the ovary 

 or .germen, containing ovules or young seeds, and the stigma, a cellular 

 secreting body, which is either seated on the ovary, and is then called 

 sessile, as in the Tulip and Poppy*(fig. 444), or is elevated on a stalk 

 called the style, interposed between the ovary and stigma. The style 

 is not necessary for the perfection of the pistil. Sometimes it becomes 

 blended with other parts, as with the filaments of the anthers in the 

 column of Orchidacese. 



Like the other organs, the pistil consists of one or more modified 

 leaves, which in this instance are called carpels (x.ag'jrbg, fruit). The 

 analogy of carpels to leaves may be deduced from their similarity in 

 texture and in venation ; from the presence of stomata, hairs, and 

 glands ; from their resemblance to leaves in their nascent state ; from 

 their occasional conversion into true leaves, as in Lathyrus latifolius ; 

 and from the ovules corresponding in situation to 

 the germs or buds found on some leaves, as those 

 of Bryophyllum calycinum. When a pistil consists 

 of a single carpel it is simple, a state usually de- 

 pending on the non-development of other carpels ; 

 when it ig composed of several carpels, more or 

 less united, it is mmpoimd. In the first-mentioned 

 case the terms carpel and pistil are synonymous. 

 Each carpel has its own ovary, style (when present), 

 and stigma, and is formed by a folded leaf, the upper 

 surface of which is turned inwards towards the axis, 

 and the lower outwards ; while from its margins are ■^'^' *"*■ 



developed one or more buds called ovules. That this is the true nature 



Pig. 405. Carpellary leaf of the double-flowering Cheriy. In this plant the pistil is com- 

 posed distinctly of one or more leaves folded inwards. I, Lamina or hlade of the leaf or 

 carpel, s. Prolongation of the midrib, n, representing the style, and ending in a circular 

 thickened portion equivalent to the stigma. 



