THE RECEPTACLE 8i 



of which are chickweed, poppy and wallflower. Those which 

 can be cut into two equal halves in one direction only are 

 zygomorphic ; for example vetch, pea and dead-nettle. 



The number of members constituting each whorl in a flower 

 is subject to much variation, but it will frequently be observed 

 that in Monocotyledons each whorl consists of three floral leaves 

 or some simple multiple of three (such as six or nine). In 

 Dicotyledons the floral leaves are usually in fours or fives. 



The pattern Slower just described consists of four distinct 

 kinds of floral leaves and is termed a complete flower. Sometimes 

 flowers are met with in which one or more entire sets of floral 

 leaves are missing — either calyx, corolla, andrcecium or gynsecium ; 

 such are spoken of as incomplete flowers : examples are seen in 

 the mangel and ash. 



S. The Receptacle. — In the Buttercup the receptacle is an 

 elongated cylindrical or conical axis and the whorls of floral 

 leaves are arranged upon it at successively higher levels, the 

 gynsecium occupying the highest and the calyx the lowest 

 points respectively, with the corolla and andrcecium between. 

 In many cases the receptacle is thicker and not so long as that 

 of the buttercup, but the relative positions of the parts upon it is 

 the same. Flowers which like the buttercup have the corolla 

 and andrcecium inserted on the receptacle at a lower level than 

 the gynaecium and free from the latter are termed hypogynoits 

 flowers, and the gynaecium is described as superior (r, Fig. 35); 

 examples are charlock, poppy and chickweed. 



In the plum the apex of the receptacle ceases to grow at an 

 early stage, but the parts below the apex grow up all round it 

 and form a hollow basin or urn-shaped structure, on the edge 

 of which the calyx, corolla and stamens are arranged (Fig. 124). 



The gynsecium, consisting of a single free carpel, is placed at 

 the bottom of the hollow receptacle (2, Fig. 35), this point being 

 the real apex of the floral axis. 



Flowers in which the corolla and andrcecium are arranged on 



F 



