•472 



Cross-fertilisation of Wheat. [nov., 



•cautions made that, in spite of the countless millions of 

 fertilisings taken place every year in each parish where wheat 

 is grown, it is an extremely rare thing to find a single case of 

 natural cross-fertilisation. The possibility of such an operation 

 being caused by bees is so exceedingly remote that it can almost 

 be said to have no existence. Because of its rarity, it may be 

 as well to put on record that in the course of the Committee's 

 work one case, or, perhaps, two, have been met with. A farmer 

 — Mr. Richard Cook, of Box, near Bath — planted in 1902 a 

 field with a mixture of Square Head's Master and Essex Rough 

 Chaff, two sorts of wheat which, from the breeder's point of 

 view, possess marked differences. When the crop matured he 

 •came across a plant with nine ears of particularly robust 

 growth. He propagated their contents (560 grains), and has 

 supplied the Committee with an ear of the progeny, which 

 certainly seems to indicate that a natural cross did take 

 •place. Extremely rare though such cases of natural cross- 

 breeding may be, it is not at all difficult to cross-breed wheat 

 artificially, and for many years this has been done. It has 

 always been obvious that such work results in the production of 

 great variations. 



It is known that if a male and female parent differing in four 

 distinct characteristics were crossed we should obtain no less 

 than eighty-one varieties, of which only sixteen would breed 

 true, so that in the third generation, if every form of this one 

 cross were followed up, we should require over 270 small plots. 

 The object of the earlier cross-breeders seems to have been the 

 creation of great numbers of variations from which they could 

 select those likely to be of use to them, but the great difficulty 

 was to get forms that would breed true. If, in the case men- 

 tioned, only sixteen out of eighty-one would breed true, and the 

 breeder had no certain indication which of the eighty-one the 

 sixteen were, the extreme difficulty of getting a sort fit for sale 

 is obvious. Of course, by a long process of selection year by 

 year, or even by chance in the first year, he might happen to 

 select a form that would breed true and so be fit for intro- 

 duction to the commercial world, but the value of hybridising 

 could not be esteemed highly under such conditions. But, 

 dating from 1901, the nature of the problem has been entirely 



