S PERM ATOPHYT A POLYGON ACEAE 419 



as that found in rhubarb, and rheotannic acid. The patience dock R. Patien- 

 tia), pale dock (R. altissimus') and curled dock (R. crispus} are troublesome 

 weeds; French sorrel (R. scutaius} is cultivated in Europe and used as a salad. 

 The presence of the silver plant of the west (Briogonunt umbellatum} is said 

 to be indicative of gold and silver. Muehlenbeckia platyclados of the Samoan 

 Islands is frequently cultivated in greenhouses. The mountain sorrel (Oxyria 

 digyna} is used as a salad plant. 



Genera of Polygonaceae 



Sepals 6; stigmas 3 2 Rumex. 



Sepals 5, occasionally 4, erect in part. 

 Achenes triangular or lenticular. 



Embryo slender curved around one side of the endosperm 3 Polygonum. 

 Broad cotyledons of embryo twisted and plaited 1 Fagopyrum. 



1. Fagopyrum (Tourn.) L. Buckwheat 



Annual or perennial; somewhat fleshy, smooth, leafy herbs with erect 

 stems; leaves petioled and alternate; hastate or deltoid flowers, small, white, 

 or greenish, paniculately-racemose, perfect; calyx 5-parted, persistent, the divi- 

 sions like petals; stamen 8; ovary 1-celled, 1 ovule, style with 3 divisions; 

 fruit an achene, 3-angled; endosperm mealy; cotyledons broad. About 6 species 

 native to the old world. 



Fagopyrum esculentum Moench. Buckwheat 



Smoothish plants; leaves hastate, abruptly narrowed above the middle; 

 sheath half-cylindrical; racemes somewhat panicled, many flowered; sepals 

 white, fragrant, with 8 honey-bearing yellow glands situated between the stamens. 



Distribution. A common escape in eastern North America. Native of 

 Eastern Europe and Western Asia. 



Fagopyrum tataricum (L.) Gaertn. India-wheat 



Annual, similar to the above species; leaves deltoid, hastate ;flowers smaller; 

 pedicel short. 



Distribution. In waste places from eastern Canada to New England. Na- 

 tive to Asia. 



Poisonous properties. Fagopyrum contains the glucoside indican C., 6 H 31 NO 17 

 found also in Nerium and other plants. The plant produces bloat especially 

 if consumed before bloom. 



Several years ago the writer received a complaint from a farmer stating 

 that the feeding of buckwheat had produced a rash upon his hogs. Feeding of 

 buckwheat and the eruptions or urticaria following are well known to veter- 

 inarians. 



Dr. Millspaugh says of buckwheat: 



Many individuals cannot partake of pancakes made fro^i the flour of the seeds without 

 experiencing a severe itching especially observed about thr large joints. A peculiarity of 

 this itching is that it occurs after the removing of the Hothing and when first retiring 

 at night. The eruption incident to and following this itc^'ng takes the form of vesicles 

 which degenerate into dry, dark colored scabs. Another symptom arising is a glutinous 

 condition of otherwise natural feces, making expulsion qu ; e difficult. Increased urinary 

 discharge is also present in many cases. 



