Xvi INTRODUCTION. 



forms a tube round the pistil, or^ if the pistil is wanting, occupies the centre of tlic 



flower. 



dmdeJpJioiiSy when so united into two clusters. The term is more especially ap 

 plied to certain Zef/Hminosfs, in which nhie stamens are united in a tube slit open on 

 the upper side, and a tenth, placed in the slit, is free. In some other plants the sta- 

 mens are equally distributed in the two clusters. 



triadeipJioitSy pe^iiadelphous, polyadelphous^ when so united into three, five, or 



many clusters, 



syngenesioiis, when united by their anthers in a ring round the pistil, the filamputs 



usually remaining free. 



didynamous, when (usually in a bilabiate flower) there are four stamens in two 



pairs, those of one pair longer than those of the other. 



tetradt/namous^ when (in Cruciferci) there are sis, four of them longer than the 

 two others. 



exsertedy when longer than the corolla, or even when longer than its tube, if the 

 Ihnb be very spreading. 



114. An Anther (109) is . ^ ^ . 

 adnate, wlicn continuous with the fdament, the anther-eeUs appearing to lie their 



whole length along the upper part of the filament. 



innate^ ^vhen firmly attached by their base to the filament. This is like an adnate 

 anther, but rather more distinct from the filament. 



versatile^ when attached by their back to the very point of the filament, so as to 

 swing loosely. 



115. Auther-cells may be parallel or diverging at a less or greater angle; or diva- 

 ricate^ when placed end to end so as to form one straight line. The end of each an- 

 ther-cell placed nearest to llie other cell is generally called its apex or summit^ and 

 the other end its hase (3G) ; but some botanists reverse the sense of these terms. 



IIG. Anthers have often, on their connectivum or cells, appendages termed bristles 

 (setic), spiirSy crests, points, glands, etc., according to their appearance. 



117. Anthers have occasionally only one cell : this may take place either by the dis- 

 appearance of tlie pai'tition between two closely contiguous cells, when these cells are 

 said to be conjluent ; or by the abortion or total deficiency of one of the cells, when 

 the anther is said to be dimidiate. 



118. Anthers will open or dehisce to let out the pollen, like capsules, m valves, pores, 

 or slits. Their dehiscence is introrse, when the opening faces the pistil j extrorse^ 

 when towards the circumference of the flower. 



lit). Pollen (109) is not always in the form of dust. It is sometimes collected in 

 each cell into one or two little wax-like masses. Special terms used in describing these 

 masses or other modifications of the pollen will be explained under the Orders where 

 they occur. 



§ 11. The PistiL 



120. Tlie carpels (91) of the Pistil, although they may occasionally assiimc, rather 

 more than stamens, the appearance and colour of leaves, are still more different in 

 shape ami structure. They are usually sessile 5 if stalked, their stalk is called a podo- 

 carp. This stalk, upon which each separate carpel is supported above the receptacle, 

 must not be.confounJed with the ggnohasis (143), upon which the whole pistil is some- 

 times raised. 



121. Each carpel consists of three parts : 



1. The Ovary^ or enlarged base, which includes one or more cavities or cells, con- 

 taming one or mure small bodies called ovules. These are the earUest condition of tho 

 future seeds, 



2. the Style, proceeding from the summit of the ovary, and supportuig — 



3. the Stigma, which is sometimes a point (or punct if arm stigma) or small head 

 (a capitate stigma) at the top of the style or ovary, sometimes a portion of its surface 

 more or less lateral and variously shaped, distmguished by a looser texture, and covered 

 with minute protuberances called papill<^, 



122. The style is often wanting, and the stigma is then sessile on the ovary, but hi 



a 



