THE POLYPETAL.E 



69 



jfficinal 



fication is the second of the above, for while many orders 

 have flo\vei*s with six stamens, not one other lias these 

 arranged in the manner they are in the Cruciferse. 



HoESE- RADISH {Cochlear la Armoracia). — A volatile 

 oil, called allyl isothiocyanate, is present in the root of 

 Horse-radish, which gives to it its pleasant pniigencj^-. 

 The oil is used in medicine as a stimulant. Its chief 

 use, however, is as a condiment, although the plant 

 figures in a list of plants required by herbalists. 



•This herb is 

 easily distinguished from others of the same order by — 



1. Its spoon-shaped leaves. 



2. Its small, globular, fleshy fruits (about 2 millimetres 



diameter). 



It stands about a foot from the ground; where growing 

 0)1 stony ground it is much smaller. 



When eaten fresh the plant is a refreshing stimulant; 

 hut formerly, as suggested by its name, far-reacliing 

 healing virtues were attributed to it. 



The Mustards. — These are by far the most important 



medicinal plants among tlie Cruciferae. There are tlu-ee 



Mustards of importance: 



Pons. 



White ^fr^sxARD ! 

 (fig. 38). 



Black Mustard 

 (fig. 39). 



Wild Mustard 



(C^AP.LOCK)({lf,^ 

 40j, 



I 



Bristly. 



foiir- 



Smootli, 

 sided. 



Rugged, 



uiaiiy angles. 



iti 



^viiri 



Lkaf. 



Deeply cut into segments from 

 the edge almost to the mid- 



r i b. 

 Lower leaves pinnate, npper 



ones narrow, pointed, nn- 



divided. 

 Rough and toothed. 



As a further help, it is useful to remember that tlie 

 Black Mustard is taller than the other two, hut its flowers 

 J^ave smaller petals. Charlock has characteristic spread- 



( 935 ) 



