OBGAKS OF REPRODUCTION. 



209 



the filament is absent, the anther is said to be sessile. The 

 staminal whorl is termed the Androecium from its constituting 

 the male system of Flowering Plants. 



The Grynoicium or Tistil is the only remaining organ ; it occu- 

 pies the centre of the flower {fig. 420, sti), all the other organs 

 being arranged around it when these are present. It consists of 

 one or more parts, called Carpels, which are either distinct from 

 each other, as in the Columbine {Aquilcgia vulgaris) [fig. 425), 

 or combined into one body, as in the Poppy {fig. 426). The 

 pistil is termed the gjjnoecium from its constituting the female 

 system of Flowering Plants. Each carpel consists of a hollow 

 inferior part, called the Ovary {figs. 425, o, and 427, d), in 

 which are placed the little bodies which ultimately by impreg- 

 nation become the seeds, called Ovides, o, o, attached to a part 

 termed the ijlacenta,^; of a Stigma, or space of variable size, com- 

 posed of lax parenchymatous tissue without epidermis, which is 



Fig. 425. 



Fig. 426. 



Fig. 427. 



Fig. 425. Gyncecium of Colnmhine (Aqnilegia vulgaris), p. Peduncle. 

 T. Thalamus, c. Carpels, each with an ovary, o ; style, sti/.; and stisina, 



stig. Fig. 426. Gyncecium of Poppy (Papaver), with one stnmen arising 



from below it. o. United ovaries, sti. Stigmas. Fig. 427. Vertical 



Bection of the gyncecium of the Pansy (Viola tricolor'', c. Calyx, d. 

 Ovary, p. Placenta. o,o. Ovules, s. Stigma on the summit of ashore 

 style. 



either placed sessile on the top of the ovary, as in the Poppy 

 {fig. 426, sti), or it is situated on a stalk-like portion prolonged 

 from the ovary, called the Style {fig. 425, sty). The only 

 essential parts of the carpel are consequently the Ovary and 

 Stigma ; the style being no more essential to it than the filament 

 is to the stamen. 



The andrcecium and gyncecium are called essential organs 

 because their presence is necessary for the production of perfect 

 seed. It frequently happens, however, that either the andrce- 

 cium or gyncecium is absent, as in the AYillow {figs. 389 and 



