230 UNIVERSITY OF MISSOURI BULLETIN 



tery and superstition in which it has been steeped for cen- 

 turies, and elevated its study to the rank of an exact science. 

 Order is rapidly entering where only chaos existed before, 

 and, although we are as yet merely on the fringe of the inquiry, 

 the measure of the advance that has been made is to be found 

 in a comparison of our understanding to-day with the almost 

 total ignorance that prevailed but a very few years ago; and 

 the method of investigation which has led us to this clearer 

 insight into the intricacies of hereditary phenomena — the 

 method of experimental research — is the only one in which the 

 hope of further success lies. 



With the means of exact analysis which Mendel's discov- 

 ery has placed in our hands, we are beginning to be able, 

 not only to clearly picture the operations of heredity, but even 

 to predict the outcome of a given mating. With increased 

 ability to foresee this result, the knowledge must surely fol- 

 low which will give to man such a power of control over 

 organic nature as is comparable only with the control that he 

 now exerts over the physical world about him. It is hardly 

 an exaggeration to say that the principle of segregation is as 

 fundamental to biology as the law of gravitation is to physics, 

 or the atomic law to chemistry ; and, although the organic phe- 

 nomena are far more complex, the hope is reasonable that, as 

 man has been enabled to apply his knowledge of physical 

 forces to the betterment of his own condition, in like man- 

 ner his understanding of heredity will lead to an analogous 

 mastery over the world of living things. Already under the 

 guidance of the Mendelian principles, the study of genetics 

 has opened to the breeder of domesticated animals and plants 

 an unlimited horizon, and has clearly indicated the path which 

 all future progress in the art must follow. 



Man himself is subject to the same laws of heredity as 

 govern the transmission of characters in other animals and 

 in plants, and, although the data at present are meagre, not 

 a few unit characters which segregate in accordance with the 



