RELATION OF BIOLOGY TO AGRICULTURE 545 



satisfactory explanation of the basis of this law will be possible only 

 after the discovery of several new facts regarding the behavior and 

 identity of the component parts of the reproductive cells. This same 

 line of research has also been suggested by the more recent development 

 of our knowledge regarding the accessory chromosome. Such research 

 demands the use of the most perfected instruments and the exercise of 

 the finest technique. It requires an impartial and truly scientific mind, 

 and it is, therefore, very gratifying to find that most of the facts being 

 added to our knowledge concerning hereditary processes in these con- 

 nections are furnished by American investigators. 



The Optimism of 1900 



Within a very few years, after 1900, numerous investigators found 

 the Mendelian law to be operative for a wide variety of characters and 

 in many species of plants. Evidence was also forthcoming to show that 

 the same was true of some characters of farm animals. 



The air was filled with expectancy, for, since so many things were 

 known to be inherited by Mendelian proportions, it was quite generally 

 assumed that all inheritance was of the same kind. Breeding was no 

 longer an art, nor even a science, but a simple application of mathe- 

 matics. True, our knowledge of the modus operandi of all these oc- 

 currences was incomplete, but Mendel's law appeared to be the key to 

 all facts of inheritance, and notliing of moment could be unknown for 

 more than a few months. Such was the thought of many enthusiastic 

 persons in 1902 and 1903. It seemed as though the great door was 

 soon to be unlocked and reveal to us the truth that should explain all 

 inheritance and all life, bringing a new era in biology and in the many 

 vital studies of man with which biology is so intimately connected. 



But even should the scientific explanation of Mendel's law be 

 slightly delayed, there was no reason for the breeder of plants and ani- 

 mals to remain under the old regime ; so it seemed to many careful and 

 earnest workers in agricultural lines. The fact that the derivation of 

 the formula was obscure was no hindrance to its utility. 



One outcome of the new thought was the organization of the Amer- 

 ican Breeders' Association. The membership of this association com- 

 prised botanists, zoologists, florists, seedsmen, growers of seed com and 

 other cereals, and also breeders of all classes of farm animals. The 

 time was ripe for such an organization. It was the idea of some of the 

 founders that the spread of the new science would revolutionize breed- 

 ing practise. 



At the second annual meeting of the American Breeders' Associa- 

 tion, held in 1905, there were presented such papers as these: " Eecent 

 Discoveries in Heredity and their Bearing on Animal Breeding." 



This paper was presented by Dr. Castle, of Harvard, a most capable 



