4 



INTRODUCTORY CHAPTER. 



The whorl within or above the corolla is the androecium (andrcecium, figs. 7, E, 

 and 10), and its leaves are stamens (stamina, figs. 10, E, and 11). The petiole of the 



stamen is the filam>nt 



(filamentum), and its blade 



is the anther (anthem). 



The dusty parenchyma 



contained in the anther is 



called pollen (pollen, p). 



This pollen leaves the 



anther at a certain period, 



and, falling on the centr.il 



organ of the flower, assists 

 in the formation of the seed. 



There frequently occur on the receptacle (fig. 10, n) small bodies (GL) which 

 secrete a sweet juice, named nectariferous glamh or nectaries (ylandnlce nectarifercr, 

 nectaria). 



The whorl within or above the andrajciuin is the pistil (pistillnm, fig. 12). This, 



3 



8. Wallflower. 



r.ih \ (in. I--. i. 



S. Wallflower. 

 PeUI. 



o 

 R. 



12. Columbine. 



Pistil eompooed of ft carpels, 

 with the scars nf the stamens 

 on the receptacle R. 



13. Coliiinblne. 



Ripe carpel puriially 



opened at the top. 



14. Pea. Hit* pis-i! 



!">. Aprirot. 



Pistil cut vertically (inn?.), showing 

 the fwmpendpd ovule i>, v. mlfrmn .-, 

 mid axis of style T, traversed by the 

 jxillen to fertilize the ovule. 



the central or last of the floral whorls, is composed of one or more leaves called 

 carpels (carpidia, carpella, fig. 13), bearing on their edges small bodies called ovules 

 (ovula), destined to reproduce the plant when fertilized by the pollen. The blade 

 of the carpel, which encloses and protects the ovules, is the ovary (ovarium,, fig. 

 12, o) ; its prolongation upwards into a longer or shorter neck is the style (stylus, T) ; 

 and the stigma (stigma, s) is an organ of variable form, spongy and viscous when 

 young, usually placed on the top of the style, and destined to receive the pollen, 

 which adheres to its surface. 



The substance of an ordinary leaf, however thin, consists of three parts : 

 (1) an upper and (2) an under surface, enclosing (3) a network of fibres and paren- 

 chyma ; and a slight inspection will show that a carpellary leaf is constructed on 

 the same plan. Thus in the Pea, the pistil of which is composed of a single carpi !, 

 which splits into halves when ripe (fig. 14), the outer portion of the leaf (E) is a 

 thin skin, easily torn away, named epicarp (epicarpium). The inner portion (EN) 



