114 Elementary Species 



sown separately, and the lots compared during 

 their whole life-period and chiefly at harvest 

 time. Three of the lots were judged of high 

 excellence, and they alone were propagated, and 

 proving to be constant new varieties from the 

 outset were given to the trade under the names 

 of *^ Shirretf's bearded white," '' Shirreff's 

 bearded red,'' and ^' Pringle's wheat.'' 

 They have found wdde acceptance, and the first 

 two of them are still considered by Vilmorin as 

 belonging to the best wheats of France. 



This second method of Shirreff evidentlv is 

 quite analogous to the principle of Lagasca and 

 Le Couteur. The previous assumption that 

 new varieties with striking features were being 

 produced by nature from time to time, was 

 abandoned, and a systematic inquiry into the 

 worth of all the divergent constituents of the 

 fields was begun. Every single ear at once 

 proved to belong to a constant and pure race, 

 but most of these were only of average value. 

 Some few however, excelled to a degTee, which 

 made them worth multiplying, and to be intro- 

 duced into trade as separate varieties. 



Once started, this new method of comparison, 

 selection and isolated multiplication was of 

 course capable of many improvements. The 

 culture in the experiment-field was improved, so 

 as to insure a fuller and more rapid growth. 



