THE DOCK FAMILY. 219 



Buckwheat {Fagopy'riun) and Ehubarb (Bhe'mn) are 

 members of this family. 



They are herbs with peculiar stipules. Each leaf 

 has two, such being usually the case with stipulate 

 leaves. They are not, however, separate, but have 

 their edges united both in front of the leaf — i.e. 

 between the blade and the stem — and on the opposite 

 side as well, making a complete sheath round the 

 stem, often with a fringed upper edge. It has been 

 called an Ochrca {i.e. a boot) (Fig. 87, 2, a). 



Ru'mex. — The common English name for the 

 species of this genus is " Dock," of which there are 

 several in South Africa. Most of the species have a 

 calyx of two whorls of three sepals to each ; there is no 

 corolla and six stamens. The ovary has three stigmas. 

 The fruit is a one-seeded nutlet surrounded by the 

 calyx, of which the three outer sepals become much 

 enlarged, carrying one or more tubercles on the back of 

 them. Two species are dioecious ; one of them is intro- 

 duced as a weed (E. Acctosel'la), known as Sheep's Sorrel. 

 The leaves are acid to the taste, like those of Ox'alis, 

 which is called " sorrel " in South Africa. 



Polyg'onum. — One of the commonest species in 

 England, and introduced into South Africa as a 

 roadside prostrate weed, is the Knot-grass (P. Avicularc) 

 (Fig. 87). 



The flowers (3) are very small. The five sepals 

 are green with a pink edge and gamosepalous. There 



