462 FLOWERS OF FIELD, HILL, AND SWAMP 



Nova Scotia to New York, southward along the mountains to 

 Georgia, westward to the Rocky Mountains, in thickets and along 

 streams. 



The mulberry-trees and osage orange belong to this family. 



47. Climbing False Buckwheat 



Polygonum scandens.—Fami/y, Buckwheat. Color, yellow- 

 ish green or whitish. Leaves, heart or halberd-shaped, pointed, 

 I to 6 inches long, with petioles and conspicuous sheaths. 



Calyx, 5-cleft, the 3 outer divisions reflexed in fruit. Sta- 

 metis, 8. Stigmas, 3. , 



A loose, straggling sort of vine, with small, dull flowers on long 

 pedicels in loose racemes. The fruit, an achene, hangs loosely 

 from the older flowers. 



In woods and thickets from Nova Scotia to Florida, and west- 

 ward. 



48. Crested False Buckwheat 



P.cristatnm is a more slender, twining species, 12 to 20 inches 

 long. Leaves, triangular, with rather sharp basal angles and 

 pointed apex, long-petioled. Flowers generally in leafless ra- 

 cemes on jointed pedicels, greenish white. 



In sandy woods and rocky banks from southern New York to 

 Georgia, westward to Tennessee and Texas. 



49. Wild Yam-root 



Dioscorea villosa. — Family, Yam. Color, greenish yellow. 

 Leaves, stalked, ovate, heart-shaped, pointed, in fours or pairs, 

 or alternate, 9- to ii-ribbed, 2 to 6 inches long. Time, July. 



Flowers small, inconspicuous, the sterile thickly clustered, 

 in panicles ; the fertile racemed ; drooping from the leaf-axils. 

 Root, large, tuberous. 



Among the twining vines which make our dense thickets is 

 this our only member of the yam family. About 150 species are 

 classified and known — mostly tropical — of which 4 form a staple 



