CHAPTER XI. — THE PISTILS, OR GYX.ECIUM. 



85 



Fig. 267. 



Fig. 268. 



Fig. 267. — Pistil of Primrose, with 

 ovary cut vertically to show free-central 

 placenlation. Enlarged. 



Fig. 268. — Pistil of Pinguicula, en- 

 enlarged and cut transversely to show 

 free-central piacentation. 



4. Those with basilar or free-central placenta. Here, the 

 ovules are borne on a column which rises free from the bottom 

 of the ovary, as in the Primrose and the Soapwort. This form 

 of piacentation is illustrated in 

 Figs 267 and 268. 



An ovary that has but one cav- 

 ity, as the Pea-pod, and as shown 

 in Figs. 256 and 264, is termed 

 unilocular ; one that, as in Figs. 

 259 and 261, has two cavities, is 

 called bilocular ; one that, as in 

 Figs. 260 and 265, has three cav- 

 ities, is trilocular ; and one that 

 has many cavities is called multi- 

 locular, or plurilocular. 



As has already been stated, 

 the ovary is often more or less 

 adherent to the calyx. When it 

 is entirely free from the latter, it is 

 said to be superior ; when partially 

 adhering, it is half -superior, or half-inferior ; and when com- 

 pletely enveloped in the adnate calyx-tube, it is inferior. 



The Style. This is the stalk of the stigma, or the part of the 

 pistil which connects the stigma with the ovary. It sometimes 

 contains a narrow canal or passage-way leading from the one to 

 the other, but more commonly this is wanting, and the interior 

 is composed of thin-walled cellular tissues. It most commonly 

 arises from the summit of the ovary, in which case it is described 

 as terminal or apical ; in some cases, however, it is inserted on 

 one side, as in the Strawberry, when it is called lateral, or it may 

 even be attached to the base of the ovary, as in Alchemilla, when 

 it is described as basilar. Very commonly the style falls away 

 after the process of fertilization is completed, in which case it is 

 termed deciduous, but sometimes it remains and forms a part of 

 the fruit ; it is then called persistent. This is the case in Snap- 

 dragon and Scrophularia. As regards its form, it may he filiform 

 or thread-like, as in the Fuchsia; clavate or club-shaped, as in the 

 Orange ; subulate or awl-shaped, as in Cyclamen ; petaloideous 

 or petal-like, as in Iris. It may also be either simple or branch- 



