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ERANCIS MARSH BALDWIN 

 TABLE IV 



(approximately 1 :4) , and again the period of greatest activity 

 of the subjects is found to lie between the hours 6-12 P. M. 



To determine the influence of food placed at the mouth of the 

 burrow on the activity of the worms three series of observations 

 were made and the results summarized in table IV. The letters 

 under ' Days ' refer to the records of three successive days, 

 before (a), while (b), and after (c) food was placed at the mouth 

 of the burrow. 



It appears from the above table that the presence of food at 

 the mouth of the burrow tends to increase the activity of the 

 worms, as indicated in the record of b. Activity is least upon 

 the day (c) following its removal. 



These observations lead us to conclude that (1) in spite of 

 individual differences the total active time, when compared to 

 the total time under observation, is fairly constant, that (2) the 

 earthworm has definite active periods, confined, for the most 

 part, to hours of the night, especially to the early hours of the 

 # night, and that (3) food has a decided effect upon activity. 



