306 THE FLOWER 



the third on some variable part of the face of the cell in the vicin- 

 ity of either suture. In Obolaria, a compound unilocular ovary is 

 ovuliferous over the whole wall of the cell.* 



558. When the styles are separate towards the summit, but 

 united below, they are usually described as a single organ ; which 

 is said to be parted, cleft, lobed, &c., according to the extent of 

 cohesion. This language was adopted, as in the case of leaves 

 (281) and floral envelopes (461), long before the real structure 

 was understood : but, as it involves an erroneous idea, the expres- 

 sions, Styles distinct ; united at the base ; united to the middle, or 

 summit, &c., as the case may be, should be employed in preference. 



559. A few casual exceptions occur to the general rule that 

 ovules and seeds are both produced and matured within an ovary, 

 namely, in a closed carpellary leaf or set of combined carpellary 

 leaves. In the Blue Cohosh, Leontice (Caulophyllum) thalictroi- 

 des, the ovules rupture the ovary soon after flowering, and the 

 seeds become naked ; and in the Mignonette they are imperfectly 

 protected, the ovary being open at the summit from an early pe- 

 riod. In all such cases, however, the pistil is formed and the 

 ovules are fertilized in the ordinary way. 



560. GynfEcium of Gymnospermous Plants, A far more important 

 and remarkable exception is presented by two natural families, 



the Conifera3 (Pines, Firs, &c., Fig. 

 391-402), and the Cycadacere (Cy- 

 cas, Zamia, Fig. 403). Here the 

 pistil, as likewise the whole flower, 

 is reduced to the last degree of sim- 

 plicity ; each fertile flower consisting 

 merely of an open carpellary leaf, in place of a pistil, in the form 



* These various points arc elucidated by Mr. Brown, in Plantce Javanica 

 Rariores, pp. 107-112, in two notes which apparently are not sufficiently 

 studied by many English botanists. All placentation is very differently ex- 

 plained by those who adopt the hypothesis of Schleiden and others. Accord- 

 ing to this new^iew, as buds regularly arise from the axils of leaves and from 

 the extremity of the stem or axis, and only in some exceptional and abnormal 

 cases from the margins or surface of leaves, so ovules are considered to arise 

 from the axis of the flower, like terminal buds, or from the axils of the car- 

 pellary leaves, like axillary buds. Thus, placentae are supposed to belong to 



FIG. 391. A carpellary scale from the ament of a Larch, the upper side turned to the eye, 

 showing the pair of ovules at its base. 392. The same in fruit, reduced in size; one of the 

 winged seeds still attached ; the other, 393, separated. 



