592 



A VERS. 



of higher animals as well as upon the simpler forms, in the 

 endeavor to discover the causes which lie back of them. 



Note i. — On p. 383, 8th line from the bottom of the page, it is stated that 

 the two pairs of constrictors are at all times equally stimulated. In this I only 

 mean to say that an equal stimulus is simultaneously applied to the nerves of 

 both muscles. To show why the muscular responses vary by changing the rate 

 is probably to solve our problem. 



Note 2. — The statement in the first paragraph on p. 389 is for me one of fact 

 merely, but I may say that Professor Bowditch is of the opinion that there is no 

 physiological reason apparent to prevent us from assuming that the results of all 

 these experiments are harmonious. 



The Lake Laboratory, 



Milwaukee, Wis., Feb. 10, 1893. 



