196 PHARMACEUTICAL BOTANY 



single carpels. In the latter the young peas occupy a double row 

 along one of the sutures (seams) of the pod. This portion corre- 

 sponds to the infolded edge of the leaf, and the pod splits open along 

 this line, called the ventral suture. 



Dehiscence, or the natural opening of the carpel to let free the 

 contained seeds, takes place also along the line which corresponds 

 to the mid-rib of the leaf, the dorsal suture. 



The gyncecium or Pistil may consist of a number of separate 

 carpels, as in the buttercup or Nymphaea flowers, when it is said to 

 be apocarpous, or the carpels composing it may be united together 

 to form a single structure, as in the flowers of Belladonna and Orange, 

 when it is called syncarpous. 



If the pistil is composed of one carpel, it is called monocarpellary; 

 if two carpels enter into its formation, it is said to be dicarpellary; 

 if three; tricar pellary; if many, poly car pellary. 



Compound Pistils are composed of carpels which have united to 

 form them, and therefore their ovaries will usually have just as 

 many cells (locules)- as carpels. When each simple ovary has its 

 placenta, or seed-bearing tissue, at the inner angle, the resulting 

 compound ovary has as many axile or central placentae as there are 

 carpels, but all more or less consolidated into one. The partitions 

 are called dissepiments and form part of the walls of the ovary. If, 

 however, the carpels are joined by their edges, like the petals of a 

 gamopetalous corolla, there will be but one cell, and the placenta 

 will be parietal, or on the wall of the compound ovary. 



The ovules or megasori are transformed buds, destined to become 

 seeds in the mature fruit. Their number varies from one to hun- 

 dreds. In position, they are erect, growing upward from the base 

 of the ovary, as in the Compositae; ascending, turning upward from 

 the side of the ovary or cell; pendulous, like the last except that 

 they turn downward; horizontal, when directed straight outward; 

 suspended, hanging perpendicularly from the top of the ovary. 



In Gymnosperms the ovules are naked; in Angiosperms they are 

 enclosed in a seed vessel. 



A complete angiospermous seed ovule which has not undergone 

 maturation consists of a nucellus or body; two coats, the outer and 

 inner integuments; and a funiculus, or stalk. Within the nucellus 



