APETAL^ 207 



of two rows of three petaloid, herbaceous segments 

 (sepals). There are two rings of stamens, three in 

 each, opposite the sepals, hypogynous, or perigynous. 

 The styles are three in number. In Mountain Sorrel 

 the parts of the flowers are in twos. In some foreign 

 types the outer stamens exhibit branching or 

 dedoublement. In the acyclic types the perianth- 

 segments are five in number, and there are five to 

 eight stamens and three styles. The sepals may be 

 free or united below, persistent, overlapping in bud. 

 The anthers are two-celled. If a disc is present it 

 is glandular and annular. The ovary is one-celled, 

 the pistil being syncarpous, and is free, ovoid, three- 

 sided, or flattened. The stigmas are pin-headed and 

 very slender. The ovule is solitary, orthotropous, 

 erect. The fruit is a triangular nut, smooth externally, 

 indehiscent, enclosed in the persistent perianth. The 

 seed is erect, wnth a membranous testa. The embryo 

 is straight and axile or lateral and curved, with mealy 

 endosperm. 



The flowers a:e wind-pollinated, or, as honey is 

 present in some cases, cross pollinated by insects. 

 The fruits are dispersed by the wind, by the winged 

 perianth. In some types the fruits are hooked and 

 dispersed by animal agency. 



There are several plants of economic importance, a 

 powdered root yielding the Rhubarb of the druggist, 

 and a species of Dock, that of the garden. The 

 leaves are acid, as in Sorrel, or astringent. The roots 

 are purgative. Buckwheat, powdered, has been used 



