ELEMENTARY SPECIES IN AGRICULTURE. 423 



pected. The slow and gradual working up of a cereal to a previ- 

 ously fixed ideal seemed to be a process of the simplest possible 

 nature. In reality, however, it is composed of a series of factors, 

 which the breeders themselves have not recognized, and which, 

 therefore, it is now often impossible to discern in their descriptions. 

 In broad lines such an analysis has been made practicable by Nils- 

 son's discoveries. Unfortunately it conduces to a less high appre- 

 ciation of the breeder's merits (Mut. Th., p. 82), but on the other 

 hand it gives a stronger support to the theory of the saltatory origin 

 of species. 



The breeding of cereals results in varieties, which are as constant 

 and independent as the best horticultural sorts. In some cases they 

 are known to originate in the same way, by accidental sports, as in 

 the instance of Beseler's oats losing their needles. Here their com- 

 plying with the principle of mutation is obvious. In the large 

 majority of cases, however, including the most renowned improve- 

 ments of cereals and other crops, they are said to have been pro- 

 duced by the common slow and gradual process of selection. All 

 such cases are surrounded with doubt, as well concerning their real 

 origin, as in view of the degree of self-dependency which is reached 

 at the end. Often practical reasons lead one to prefer the original 

 seed to one's own harvest, especially when it is difficult to keep the 

 cultures clean from vicinistic impurities. A race, which is really self- 

 dependent, may in this way seem to be permanently related to the 

 continuous selection of its pedigree. It is especially in Germany 

 that this method of slow amelioration is much beloved and has given 

 admirable results. One of the best known instances, and for which 

 the historical records are the most complete, is the renowned rye of 

 Schlanstedt, produced by Rimpau, which is now largely cultivated 

 all over the central parts of Germany and the northern districts of 

 France. In the year 1876 I had the privilege of visiting Mr. Rimpau 

 on his farm at Schlanstedt and of studying his cultures. The 

 choicest of his new rye occupied a small patch out on the fields, 

 but surrounded by cultures of vegetables and other plants not 

 belonging to the cereals. These minor cultures occupied a large 

 square, which in its turn was surrounded by a complete range of 

 shrubs. Thus the rye, standing in the midst of the square, was suffi- 

 ciently hidden from possible contamination by pollen of other 

 varieties. On the other hand, it was given the same soil and exposure 

 and almost the same cultural treatment as the average cultures. 



This race had been started by Rimpau nine years before, in the 



