37 



same time possessing the strength of straw of the Imperial. Thousands of 

 plants were examined and out of these a few dozen were discovered which 

 showed the desired character. These were planted out in separate cultures 

 and their progeny studied with the result that eight years later (1901) the 

 progeny of one of the best of these came on the market under the name 

 Svaldfs' Primus, (0706). 



The above account has been cited by DeVries (79) "as an illustration 

 of the high significance of these correlations," a citation which has been 

 widely quoted in America. An examination of the origin of the mother sort 

 from which Primus was taken, however, seems to throw an entirely different 

 light on the situation and to nullify the arguments presented as to the value 

 of correlations, at least in so far as this particular case is concerned. Thus the 

 so-called " Imperial " barley referred to as the mother variety of Primus was 

 imported from Germany for testing at Svalof under the name Diamond. 

 This was originated by Bestehorn of Germany and listed in the German seed 

 catalogues as a crossing product of certain parentage. The opinion that this 

 sort was actually of hybrid origin was expressed by Bolin (5, p. 61) in 1893 

 and later (7, p. 10) was more fully discussed by the same author in one of the 

 leading periodicals of Sweden, substantially as follows: 



"Among the various barley sorts imported from Germany for testing 

 at Svalof was one known as the Diamond barley. This was said to be a cross- 

 ing made by Bestehorn, a German breeder, between a Nutans form (probably 

 Chevalier) and Imperial which belongs to the Erectum type. The hybrid 

 Diamond was found to be mixed (unfixed) the majority of the plants resemb- 

 ling Chevalier. Among the whole population were found a few plants, the 

 kernels of which showed a union of the short woolly-haired rachilla of the 

 Chevalier with the peculiar character of the base of the kernel of Imperial 

 and thus were regarded as the result of a true crossing between the two. The 

 plant from which Primus originated was one of these" 



If this sort is actually a crossing product, as Bolin insists, it affords an 

 excellent example of the value of hybridization as an aid to the breeder. At 

 the same time the circumstances which surrounds its origin, together with 

 the fact that sorts which have the supposedly undesirable character of kernel 

 have proven quite as satisfactory for brewing as have those which were re- 

 garded as especially suitable for this purpose, deal a severe blow to those who 

 have sought to show the importance of correlations in forming direct judg- 

 ments as to practical values. 



Speaking of these correlations in barley Tedin says : " I do not believe in 

 the existence of correlations between different simple characters by which a 

 certain character is said to indicate the nature of another, but regard such as 

 being simple manifestations of the same unit-character" (73, p. 8-9). 



The inability to judge practical qualities from other characters in ac- 

 cordance with the idea of correlations is also pointed out by Johannsen (16), 

 K^lpin Ravn (58) and other workers of recent years. 



In Denmark important investigations into the question of correlations 

 have been prosecuted for many years. A few examples will here be cited. 

 As is well known by all breeders, different pure-lines or strains have their 



