70 :\[EDICIXAL HERr.S AND POISOXOUS PLAXTkS 



ing Hepals, and Is very abundant in cornfields. Another 

 useful point to remember is that the seeds of the White 

 Mustard are 2 milHmetres, and those of the Black Mus- 

 tard 1 millimetre in diameter. 



The pcsydered seeds are used for making poultices. 

 " Mustard leaves" consist of paper to the surface of which 

 the crushed seeds (deprived of fixed oil) l^ave been made 

 to adhere. 



Fiff. S8.— White Mustard 



Fig. 39, -Black ^rnstartl 



The innocence or guilt of the Charlock in producing 

 injurious effects is an important matter, owing to its 

 abundance in cornfields, and the consequei^t risk of its 

 appearing later in flour and ultimately in our bread. 

 A really poisonous Crucifer is, however, unknown, and 

 Cliarlock, notwithstanding Linna}us' comment on it, is 

 quite an innocent plant. 



Altliough Mustard was cultivated in this countrj^ before 

 the "War, most of our supplies came from the Continent, 

 indicating that Ave Iiad not attended sufficiently to the 

 cultivation of an essentially native, medicinal plant. 



As a family the members of the Cruciferce neither 



