AND ANIMAL LIFE. 259 



effects, without endangering the life of the ani- 

 mal. The influence of opium in these instances 

 does not lessen the generation of animal heat, 

 nor disturb the respiratory function to the same 

 extent as the division of the par vagum in those 

 cases in which the tube is not inserted into the 

 trachea ; and in accordance with this difference 

 in degree, we observe that the changes in the 

 stomach and intestines are more complete, and 

 the lungs do not show the same traces of disease. 

 I have noted the state of the respiration at the time 

 when the animal temperature was taken ; but the 

 reader must not imagine that the number which is 

 given is to be considered as a criterion of the char- 

 acter of the respiration prevailing for more than a 

 few minutes or seconds, but merely as presenting 

 to the mind an idea of the irregularity of respira- 

 tion. Messrs HOLROYD and MURRAY kindly 

 assisted me in these experiments. 



R 



