POLYGONACE^ 289 



sistent style. The seeds are three-angled, conforming in 

 shape to the fruit; the testa is thin and red; the hilum and 

 micropyle are basal; the endosperm is abundant and sur- 

 rounds the large, straight embryo. Good-sized plants can 

 be raised from seed in one season if it is planted early. The 

 seedlings of rhubarb show interesting variation. 



Geographical, and Varieties. — The common rhubarb is a 

 native of Asia. It has become introduced into many coun- 

 tries of the temperate chmates. It is a cool season crop that 

 will withstand summer heat, and the roots winter freezing. 

 It is claimed that a number of the varieties now grown 

 are hybrids between R. rha'ponticum, R. undulatum and 

 R. palmatum. The principal varieties grown are Linnaeus, 

 Victoria and Monarch. There are a number or ornamental 

 species of Rheum, most of which are distinguished from com- 

 mon rhubarb by their more or less lobed leaves, the margins 

 of which may be coarsely or finely toothed. 



Uses. — Rhubarb or pie plant is a vegetable used for its 

 large, acid leaf stalks, which are of the best quahty early in 

 the season. The leaf stalks are usually made into pies or 

 sauce, and occasionally wine 'is made from the juice. 



FAGOPYRUM VULGARE (Common Buckwheat) 



Roots. — Common buckwheat is an annual, from 2 to 4 feet 

 tall. It has a small root system. There is a single primary 

 root which may reach down to a distance of 3 or 4 feet; side 

 roots are given off along the primary, but they do not extend 

 far into the soil. Buckwheat differs from the true cereals, in 

 the possession of a single primary root, and a much less 

 extensive root system. 



Stems. — The stems are quite succulent, smooth, except at 

 the nodes, and strongly grooved. Each seed gives rise to but 

 one stem which may branch freely, but, unlike grasses, no 

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