[mcmurrich] presidential ADDRESS 5 



and from collecting more or less chance data illustrative of heredity 

 and variation, investigators began to carry on experimental studies of 

 these phenomena. The rediscovery of Mendel's observations made 

 in the sixties gave additional stimulus to these studies, and to-day 

 active and accurate experimental studies are revealing the general 

 applicability of Mendel's laws and are 3àelding a sure basis for the 

 control of inheritance by selection to an extent hardly dreamt of a few 

 years ago. Nor should it be forgotten that from such studies a scien- 

 tific basis is being established for the investigation of the principles of 

 Eugenics, whereby it is to be hoped that important study may be 

 rescued from the unfortunate position that threatened it at the hands 

 of unscientific and overzealous enthusiasts. 



Refinement of technique has also led to specialization by the 

 development of special methods suitable only to certain tissues. The 

 study of the nervous system has thus become a special field in which 

 progress is possible only for those trained in the special methods 

 necessary for its elucidation, just as the seience of Bacteriology has 

 branched off from Botany of which it formed a part when Cohn and 

 DeBary were conducting their classical studies on the lower fungi. 

 And remarkable have been the results that followed these new depar- 

 tures. Fritsch and Hitzig in 1871 laid the foundations for a scientific 

 study of cerebral localization upon which later workers have built 

 securely, giving us a new phrenology to which Flechsig has added the 

 doctrine of association centres that makes intelligible to us the signi- 

 ficance of what were termed the "silent areas" of the brain. Golgi 

 and Waldeyer with the neurone theory have brought order out of 

 chaos, disentangling the apparently inextricable network of the 

 myriads of cells and fibres of which the nervous system is composed, 

 and on this foundation exi^eriment and experience have builded until 

 it is now possible to determine with great exactness the paths followed 

 by various stimuli until they result in consciousness. Furthermore the 

 influence of the doctrine of evolution reacted also on Psychology, and 

 the evolution of animal behaviour took its place among the lines of 

 investigation followed by zoologists, the study of the comparative 

 psychology of forms belonging to all zoological groups clearing greatly 

 our ideas as to volitional and instinctive reactions, as well as throwing 

 light on the evolution of adaptive responses. 



Finally, the study of the effect of abnormal and artificial environ- 

 ments has led in recent years to a revival of œcological studies, studies 

 of the enviromnental factors that make for the success of any species 

 in the struggle for existence and the effect of natural changes in the 

 environment in modifying œcological associations. The importance 



