10 



FIELD AND WOODLAND PLANTS 



ma^ grow from immediately below the pistil, or from its summit ; 

 or they may be attached to either the petals or the sepals. The 

 filaments are usually distinct, but sometimes they are united in 

 such a manner as to form a tube, or grow into two or more bundles. 

 The anthers are usually distinct, even when the filaments are united ; 

 but these sometimes grow together. 



The central part of the flower is the pistil, and this is made up of 

 one or more parts called carpels. Each carpel, when distinct, is a 

 hollow case or ovary, prolonged above into one or more stalks or 

 styles, tipped by a viscid secreting surface called the stigma. The 

 ovary contains the ovules, attached to a surface called the placenta ; 

 and these ovules, after having been impregnated by the jDollen, 



develop into seeds which 

 are plants in embryo. 

 The ovary may have no 

 style, and the stigma is 

 then sessile. 



Where the pistil con- 

 sists of more than one 

 carpel, these carpels may 

 unite in such a manner 

 as to form a single cell, 

 or an ovary of two or 

 more cells. In other 

 cases the carpels remain 

 quite distinct, thus form- 

 ing a number of distinct 

 ovaries, each with its own stigma. For purposes of identification 

 it is often necessary to note the position of the placenta. This 

 may be at the side of the ovary, in which case it is said to be 

 parietal; or it may stand up in the centre of the ovary, with- 

 out any attachment to the sides, when it is described as free 

 central. If, however, it occupies the centre of the ovary, but is 

 attached by means of radiating partitions to the sides, it is 

 termed axile. 



If the ovary is quite free in the centre of the flower, the sur- 

 rounding parts being attached below it, it is said to be superior; 

 but if the perianth (p. 11) adheres to it, it is inferior. 



A leaf or scale will often be observed at the foot of a flower 

 stalk or at the base of a sessile flower. This is termed a bract, and 

 a flower possessing a bract is said to be bracteate. The bract is 



LONGrrUDINAL SECTION THROUGH THE FLOU^ER 

 OF THE BUTTERCUP 

 Showing the calyx, corolla, stamens, and pistil. 

 The pistil consists of several distiiict carpels, 

 one of which is represented in section to show 

 its single ovule. 



