8 ROYAL SOCIETY OF CANADA 



Cask XIV.— .S7. Berncn-d piqjpy : lôth day.— Eyes open. Ether. 



Negative to any strength of current: this applies to both cortex and 

 medulla; both sides of brain tested. 

 Cask XV. — St. Bernard pujypy, name litter ; .'Sf/i day. — Ether. 



With current C get movements of head, of fore-leg and of hind-leg when 

 diflerent areas are stimulated. The order given serves to indicate the readi- 

 ness and perfection of the different movements in this case. 

 Cask XVI. — Gordon Setter bitch-picppy ; .!^nd day.— Ether. 



With current B, movement of the fore-legs; with a slightly stronger cur- 

 rent, movement of the hind-leg ; where the strongest current used, both legs 

 at times move together, and the head is also moved (to the opposite side). 



General Remarks on the Experiments ox Dogs. 



Ill these and Ciises of other animals used, onl}- those have been reported 

 in which the conditions were favourable, unless it has been otherwise 

 stated. Eosults, or the lack of positive results, ai-e, as before mentioned, 

 of no moment Avhen h?eniorrha^-e is excessive, when the narcosis is very 

 profound, or when all but absent, speaking generally. Occasionally 1 

 havi' notice(l that movements may be obtained in spite of severe haemor- 

 rhage, prolonged exjiosure of the brain, frequent stimulation, etc., and 

 while such results are highly instructive, they do not bear so directly on 

 the questions — At what period is there first cortical localization of any 

 kind ? and In what order are the centres functionally developed ? — 

 which were the main problems of this research. 



The experiments reported are against any sort of cortical localization 

 before about the tenth to the thirteenth day, though Case T. seems to be 

 an exception, unless we assume that the result was owing to the conduc- 

 tion of the current to the white matter beneath. This suljject will be 

 considered later. 



Case II. seems to show an advance' in the cortex. The ï-esult on 

 siidving the electrodes deeply into the brain is one to which I should hesi- 

 tate to attach much im])Ortance as indicating the superior functional 

 activity of the medulla at this period, considering the strength of the 

 current. 



Casein, is interesting in illustrating the advance made in a single 

 day. It also seems to indicate that some of the results are due to dif- 

 fu.sion of the current. 



The medulla giving a negative reaction in this ca.se is to be cxjilained. 

 I think, wholly on the ground of unfavourable conditions, such as hu'iiior- 

 rhage. trial after the brain had been exposed for some time, etc. 



From such a case as Y., taken by itself, it is impossible to come to 

 any conclusion as to localization ; for the movement resulting from 

 stimulation seemed to be in no wi.se better when the medulla was in ques- 

 tion than when the cortex was tested. 



Case IV. includes both an advance and faii'h' distinct localization ; 



