THE PISTIL. 



71 



(fig. 411, T) ; it is this tissue, which, spreading over the top or sides of the style, 

 forms the spongy surface called the stigma (s). The same tissue descends from the 

 style into the cavity of the ovary (fig. 412, TO), passes along the placentas (PL), 

 and covers with its loose cells the rnicropyle of each ovule (G) ; and it is between 

 these cells (fig. 413) that the pollen-tube, leaving the pollen-grain on the stigma, 

 effects a passage to and fertilizes the ovule. 



In Composites, the conducting tissue consists of two threads (fig. 414, C.p, C.p), 

 which descend from the base of the style upon the sides of the ovule, without 

 adhering to it ; at its base they join and enter the base of the funicle, near the 

 micropyle. 



In Statice (fig. 415), according to Mirbel, the conducting tissue 

 (tis. c) resembles a pestle ; it enters the cavity of the ovary, im- 

 mediately above the gaping micropyle of the ovule (ov.), which 

 is suspended from a basal cord (cor.). This conducting tissue rests 

 on the micropyle like the stopper of a decanter, and is visible 

 after fertilization (fig. 416). 



tis.c 



415. Statice. 

 Ovary cut vertically, 

 showing the ovule before 

 fertilization (mag.). 



416. Statice. 



Fertilized 

 ovule (mag.). 



422. Parietaria. 

 Pistil (mag.). 



418. 

 Tobacco. 



Pistil. 



419. 



Wallflower. 

 Pistil (mag.). 



The stigma (figs. 413 and 411 s) is nothing but the conducting tissue spread out; 

 the sfigmatic surface has no epidermis, and is usually spongy, damp, and papillose, 

 and thus suited to retain the pollen. 



The stigma (whether simple or compound) is complete (st. com- 

 pletum) when it is continuous with the style, and clearly distin- 

 guishable. The complete stigma may be globular (Daphne, fig. 417), 

 hemispheric (Primrose, fig. 376), round (Tobacco, fig. 418), forked 

 (Wallflower, fig. 419), bi-lamellate (Datura), lobed (Lily, fig. 375; 

 Melon, fig. 420), laciniate or 

 fringed (Saffron, Rumex, fig. 

 421), penicillate (Parietaria, 

 fig. 422), plumose (Wheat, fig. 

 423), discoid, conical, cylindric, 

 club-shaped, awl-shaped, &c. 

 It is superficial (st. super- 

 ficiale) when confined to the surface of a part of the style or ovary, and only 



425. Ranunculus. 

 Carpel (mag.). 



423. Wheat. 

 Flower (mag.). 



