54 



tion is called axile. In some cases the ovules are borne on a 

 central axis which is not connected by dissepiments with the 

 walls of the ovary and the pistil is consequently one -celled. 

 The placentation in such cases is called free-central. 



As a rule the ovules are borne on the margins of the 

 carpels, but in some cases they are developed all over the 

 internal face of the carpels and the placentation is then 

 called superficial. 



In a compound pistil the styles may, or may not, be more 

 or less completely combined and the number of styles, or of 

 the divisions of the style, or stigma, often indicates the 

 number of carpels in the pistil. 



Owing to one side of the ovary growing more rapidly 

 than another, the style sometimes becomes displaced to one 

 side and appears to arise from the base instead of from the 

 apex of the ovary. Such a style is said to be qynobasic. 



In some cases the floral receptacle, or torus, is prolonged 

 upwards between the carpels forming a kind of beak to which 

 the ovaries and styles adhere and from which they separate 

 when the fruit ripens. Such a beak is called a carpophore. 

 Characters 51. The rounded out-growths 



of Ovules. O f -f/kg car p e i s wn ich are destined to become the seeds 

 are called ovules. These may be sessile, or they may be 

 provided with a distinct stalk called the funicle. A 

 typical ovule consists of a central portion of soft tissue 

 called the nucellus which is invested with one or two coats 

 called the integuments. The latter do not completely cover in 

 the nucellus, a narrow hole being left at the apex which is 

 called the micropyle. The spot from which the integuments 

 originate at the base of the ovule is called the chalaza. 



Ovules are : 



erect, when they rise from the base of the ovary ; 

 ascending, when they rise obliquely and are attached near 



the bottom of the ovary ; 

 horizontal, when they are borne on the side of the 



ovary with their long axis horizontal ; 

 suspended, when hanging from the apex of the ovary; 

 pendulous, when hanging obliquely from near the apex 



of the ovary; 

 orthotropous, when they are straight, with the chalaza 



and micropyle in one straight line and the chalaza 



at the apex of the funicle , 

 campylotropous, when the line joining the chalaza 



and micropyle is curved, the micropyle being brought 



