Section IV., 1899. [ 167 Trans. R. S. C. 



Vll.— On some points on the Physiology of the brain of the Bird. 

 By AVesley Mills, M.A., M.D.,Prof. of Physiol o<,^y in McGill University 



(Read May 26Lh, 1899). 

 I 



The present is a short preliminary note on work not yet completed. 



The author is re-investigating the whole question of cortical cere- 

 bral localization in the pigeon, on which subject a communication was 

 previously made to the society. 



He has also been engaged upon the examination of the results of 

 removing greater and less portions of the cerebrum, and these were illus- 

 trated by two pigeons which were exhibited to the section. Of these 

 one had suffered the loss of the greater part of the cerebrum about six 

 months previously. This bird was capable of all the ordinary move- 

 ments of the natural pigeon. It did not, however, eat voluntarily, but 

 would swallow when food was put into its mouth, and would drink 

 when its beak was dipped into water. 



Its trophic condition was depressed, as shown by its general appear- 

 ance, by a diseased condition of the mouth, with but a slight tendency 

 to yield to treatment, and by loss of weight, in ^ite of the administra- 

 tion of specially nourishing food, etc. 



There never has been any signs of paralysis or in-coordination of 

 muscular movements. 



In a second pigeon operated upon about three months ago, the 

 condition is considerably different. From this bird only the posterior 

 half of the cerebrum was removed. After a few days it began to eat and 

 drink, and has fed as an ordinary bird ever since. It is, as may be seen 

 in excellent condition, its appearance being in marked contrast to that 

 of the other bird. 



Its movements are to ordinary observation indistinguishable from 

 those of a normal pigeon ; indeed, this applies to its entire life, somatic 

 and psychic. 



It is proposed to keep these birds alive for some time yet, and to 

 continue to record the condition frequently in the future as in the past, 

 and further efforts will be made to improve the nutritive condition of 

 the one requiring it. Both birds will be kept under identical condi- 

 tions for comparison, as in the past. 



The operations on these birds were of course carried out under an 

 anaesthetic, and antiseptically. The wounds healed rapidly, and they 

 have never suffered any pain so far as can be observed. 



