OUTLINES OF BOTANY. xiii 



fdiadelphous, when so united into' two clusters. The term is more especially applied to 

 certain Leguminosa, in which nine 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 stamens are equally 

 distributed in the two clusters. 



tnadelplwus, pentadelphaus, polyadelphous, when so united into three, five, or many clusters. 



syngenedous, when united by their anthers in a ring round the pistil, the filaments 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. 



tetradynamous, when (in Crucifera) there are six, four of them longer than the two others. 



exserted, when longer than the corolla, or even when longer than its tube, if the limb be 

 very spreading. 



114. An Anther (109) is 



adnate, when continuous with the filament, the anther-cells appearing to lie their whole 

 length along the upper part of the filament. 



innate, when 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. Anther-cells may be parallel or diverging at a less or greater angle, or divaricate, when 

 placed end to end so as to form one straight line. The end of each anther-cell placed nearest 

 to the other cell is generally called its apex or suvtmit, and the other end its base (36) ; but some 

 botanists reverse the sense of these terms. , 



116. Anthers have often, on their conneotivum or cells, appendages termed bristles (setsB), 

 spurs, crests, points, glands, etc., according to their appearance. 



117. Anthers have occasionally only one cell ; this may take place either by the disappearance 

 of the partition between two closely contiguous cells, when these cells are said to be confluent; 

 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, in valves, pores, or slits. 

 Their dehiscence is introrse, when the opening faces the pistil ; extrorse, when towards the 

 circumference of the flower. 



119. 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. The carpels (91) of the Pistil, although they may occasionally assume, rather more 

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

 structure. They are usually sessile ; if stalked, their stalk is called a podocarp. This stalk, 

 upon which each Separate carpel is supported above the receptacle, must not be confounded with 

 the gynobasis (143), upon which the whole pistil is sometimes raised. 



121. Each carpel consists of three parts : 



1. The Ovary, or enlarged base, which includes one or more cavities or cells, containing 

 one or more small bodies called ovules. These are the earliest condition of the future seeds. 



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



3. the Stigrma, which is sometimes a point (or punctiform 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, distinguished by a looser texture, and covered with minute 

 protuberances called papillm. 



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

 pistil there is always at least one ovule in the ovary, and some portion of stigmatio surface. 

 Without these the pistil is imperfect, and said to be barren (not setting seed), abortive, or 

 rudimentary (84), according to the degree of imperfection. 



128. The ovary being the essential part of the pistil, most of the terms relating to the 

 number, arrangement, etc., of the carpels, apply specially to their ovaries. In some works each 

 separate carpel is called a pistil, all those of a flower constituting together the gyncecium ; but 

 this term is in little use, and the word pistil is more generally applied in a collective sense. 

 When the ovaries are at all united, they are commonly termed collectively a compound ovary. 



124, The number of carpels or ovaries in a flower is frequently reduced below that of the 

 parts of the other floral whorls, even in flowers otherwise symmetrical. In a very few genera, 

 however, the ovaries are more numerous than the petals, or indefinite. They are in that case 

 either arranged in a single whorl, or form a hea,cl or spike in the centre of the flower, 



125. The terms monogynons, digynous, polygynauis, etc, (with a pistil of one, two or more 

 parts), are vaguely used, applying sometimes to the whole pistil, sometimes to the ovaries alone, 

 or to the styles or stigmas oijly. Where a more precise nomenclature is adopted, the flower is 



monocarpellary , when the pistil consists of a single simple carpel. 



bi-, tri-, etc., to poly-carpellary , when the pistil consists of two, three, or an indefinite 

 number of carpels, whether separate or united. 



