72 KEY AND FLORA 



6. P. dumetorum L. False Buckwheat. Perennial. Stems slen- 

 der, twining, branched, 2-10 ft. long. Leaves ovate, taper-pointed, 

 heart-shaped to halberd-shaped at the base, long-petioled. Stipules 

 cylindrical, truncate. Flowers in axillary, more or less compound and 

 leafy racemes. Calyx greenish- white, the outer lobes winged and form- 

 ing a margin on the pedicel. Stamens 8. Stigmas 3. Akene 3-angled, 

 black, smooth, and shining. Margins of fields and thickets.* 



III. FAGOPYRUM Hill 



Smooth annual herbs, with more or less triangular leaves ; 

 the sheathing stipules cylindrical or funnel-shaped. Mowers 

 bisexual, white, greenish or tinged with rose color, in terminal 

 or axillary, often panicled, racemes. Calyx petal-like (Fig. 14), 

 6-parted. Stamens 8. Styles 3, with knobbed stigmas. Akene 

 3-angled, much longer than the persistent calyx (Fig. 14). 



A B C 



Fig. li. Buckwheat (Fagopyrum esculentum) 



^, flower; 5, section of flower; C, fruit. (All somewhat magnified.) 

 (After Marohaud) 



1. F. esculentum Mcenoh. Buckwheat. Annual, nearly smooth. 

 Leaves halberd-shaped, 1-3 in. long. Flowers white or nearly so, with 

 8 yellow nectar-bearing glands between the stamens. Old fields and 

 thickets, escaped from cultivation. Introduced from Europe or west- 

 ern Asia. 



26. CHENOPODIACE.S;. Goosefoot Family 



Herbs or shrubs. Leaves simple, alternate, without stipules. 



Flowers small, actinomorphic, either bisexual or more or less 



monoecious or dioecious. Calyx free from the ovary. Corolla 



wanting. Stamens usually 5, opposite the sepals. Styles or 



stigmas generally 2. Fruit with 1 seed, usually inclosed in a 



small, bladdery sac, sometimes an akene. 



