CHAPTER XLV. 



FARM 'SEEDS': SPECIAL, 



After discussing the characteristics of seeds in general, it is 

 important to mention the peculiarities of the chief farm seeds 

 in greater detail, dealing with their size, form, purity, germina- 

 tion capacity and other features, which are useful in enabling us 

 to recognise the seeds, and to separate good samples from bad 

 or doubtful ones. They will be mentioned under their Natural 

 Order. For further information in regard to the structure of 

 the flower, fruit and other parts of the plants mentioned, the 

 student is referred to Part IV. 



CRUCIFER.a;. — The chief cultivated plants belonging to this 

 Order met with on a farm, are the cabbage and its varieties, 

 swede, turnip, rape and black and white mustard. In all of 

 them true seeds are sown for a crop. 



Cabbage (Brassica oleracea L.). — This plant is one which has 

 given rise to a large number of varieties, those with which we 

 are more immediately concerned being the drumhead cabbage, 

 thousand-headed kale and kohlrabi. Other modifications, such 

 as brussels sprouts, cauliflowers and savoy, are usually confined 

 to garden husbandry. 



Form and Size. — The seeds of the cabbage and all its varieties 

 are round or oval in shape, the position of the radicle of the 

 embryos and edges of its cotyledons being indicated on the out- 

 side of the seed coat by two shallow furrows with a raised part 

 between them. The size is very variable, seeds of all diameters 

 between 1*2 to 27 ram. being met with even in the same sample, 

 and no certain distinction either of form or size can be drawn 



between the different varieties. 



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