282 PLANT-BREEDING 



vetches have been isolated at Svalof. In some of them the 

 flowers ate white, in others pink, instead of being purplish, 

 as in the ordinary sorts. The seeds may be spotted or not, 

 of a dark or of a pale hue. The spots are small, isolated, and 

 rounded in some varieties, but in others they radiate from 

 the hilum like tongues of flame. Minor marks are afforded 

 by the size and shape of the leaves, the length and mode of 

 branching of the stems, the distribution of the pods along 

 the branches, and so forth. All these marks are constant, 

 as soon as cultures are made, each starting from a single 

 parent plant. An elaborate system of the vetches has been 

 derived from them, and the single types are now being cul- 

 tivated separately, in order to examine their industrial 

 value. 



Similar investigations have been made for clover. The 

 Spanish or red clover was formerly imported into Sweden 

 where the first work has been the controlling of the value 

 of introduced sorts and of their fitness for the Swedish 

 climates. American sorts of clover proved too susceptible to 

 the hardships of the Swedish winters, but many of the kinds 

 of Middle Europe were resistant enough to be cultivated with 

 success. The red clover is very variable, in respect to the 

 shape, and size, and color-designs of its leaves, as well as to 

 the flowers and flowerheads and especially in the colors 

 and qualities of the seeds. A great number of types could 

 easily be isolated. This richness in forms and the constancy 

 of the isolated types had already been studied in several 

 other countries, as, for instance, by Schribaux in Paris, and 

 by Martinet in Geneva, and their different commercial value 

 had clearly been pointed out. But by means of the method- 

 ical study of the botanical characters, which is the principle 

 of the work at Svalof, a far larger number of types could 

 be isolated and varieties be originated which complied with 

 all the divergent demands of the soils and climates through- 





