92 Cole Crops 



of them are separated by some botanists in the genus Sinapis. 

 Therefore it is best to consider all these plants together, in 

 this account mentioning only the kinds of common cultiva- 

 tion. These brassicaceous plants are difficult to define botan- 

 ically, and the wild prototypes of some of them are not 

 definitely known. Botanists differ in their interpretation of 

 them. They are plants of immemorial domestication, and have 

 been vastly modified. 



Brassica. Cruciferw. About 40 species (if Sinapis is 

 included) of annual, biennial and perennial herbs, of Europe 

 and Asia, some of them iio-w widely spread throughout the 

 world as weeds. The table mustard of commerce is made 

 from the seeds of some of the species. The botanical charac- 

 ters of separation between the species lie to an important 

 degree in the size, shape and position of the pods, and in the 

 shape and length of the beak or top end of the pod beyond the 

 valves or detaching sides. The seeds in these plants are 

 globular in general form, without conspicuous surface mark- 

 ings; they are essentially black in the cole plants and turnips, 

 but may be brown or lighter colored in the mustards ; they 

 weigh 1 to 5 mg. and the vitality is about 4 or 5 years. Of 

 the cole plants, including rutabagas, the average seeds are 

 approximately 3 or 4 mg. in weight ; of turnips about 2 mg. 



A. Plant glaucous-blue or blue-green (varying to red), the foliage usu- 

 ally thick and more or less fleshy, the mature leaves glabrous; larger 

 leaves on the flowering stems usually clasping: flowers large (1/3 

 to 1 in. long), whitish yellow, cream-yellow or ochroleucous, the 

 petals long-clawed, sepals mostly firmly erect and not spreading. — 

 COLES. 

 B. Flowers large ("mostly exceeding 5^ in.) and very light colored 



(sometimes almost white), the inflorescence elongated at anthesis 



(4 to 10 in. long). 



Leaves large, mostly thick: stem not thickened. 



1. B. oleracea. 

 Leaves relatively small, thinner: stem tuberous. 



2. B. caularapa. 



BB. Flowers smaller (not exceeding '/i in.), yellower, the part of 

 the inflorescence in bloom at any time rarely exceeding 2 or 

 3 in. and usually shorter than this. 



3. B, campestris. 



