486 SCIENCE PROGRESS 



Charlock, the yellow mustard-like pest in potato, corn, and 

 other fields, has a seed very like turnip or rape, and often, 

 apart from taste, needs the microscope for identification. At one 

 time charlock was largely mixed with turnip or rape, and often, 

 to hide its presence in the seed, was killed before mixing, to 

 prevent its appearance in the field, on the principle, as was well 

 stated, that " dead men tell no tales." Owing to the tendency of 

 turnips and swede to bolt, the general similarity in appearance 

 in the seeds of turnip, swede, rape, and charlock (all members 

 of the genus Brassica), and to the consequent danger of fraud, 

 cases occur every year, in my own experience, in which the 

 Seed-testing Station is called in to decide as between buyer and 

 seller. The clovers at one time were far from being genuine. 

 Nobbe quotes a letter from a Continental firm offering to a 

 seedsman quartz stones so agreeing in size and colour with red 

 clover or white clover that the ordinary farmer could not distin- 

 guish them. English red clover has a high value in the trade, 

 but every season is not favourable to the general maturing of 

 its seeds. The supply falls short of the demand, and other less 

 hardy red clovers are liable to be substituted. In such cases 

 the genuineness is generally ascertainable by examination of 

 the seed impurities. 



Several seeds in falsely called English red clover are foreign, 

 and never occur in England. By the examination of such 

 impurities Stebler of Zurich has, during the past twenty years, 

 collected most valuable information as to the country of origin 

 of seeds, and his results are now in course of publication. 

 Advantage of the knowledge of this means of identification is 

 sometimes taken by the grower. Thus Russian flax seed, which 

 has a reputation for strong growth, has a common impurity 

 called " false flax " (Camelina sativa). The grower of flax in 

 another country, knowing this, sometimes introduces a little 

 false flax seed into his flax seed to give the impression that the 

 seed is genuine Russian-grown. The meadow grasses (Poa sp.) 

 differ greatly in value. The seeds of the different species possess 

 definite botanical characters, but these characters can be so far 

 removed by cleaning-machinery that the cheaper, more easily 

 obtained seed can be substituted for the dearer, better kind. 

 The ordinary buyer could not be expected to know the differ- 

 ence. Must he then continue to be, because of his unavoidable 

 ignorance, the possible victim of fraud? 



