[1911] 



Larva of Calosoma Sycophanla. 



175 



ping paper 18 inches wide. The larva was placed in the center 

 of the table and a record of its travels was made with a lead 

 pencil. 



At 8:30 A. M., June IS, a newly hatched larva was placed in 

 the center of the table by Mr. C. W. Collins, and the record was 

 kept throughout the day with the assistance of Mr. R. G. 

 Smith. The table had been placed in an attic room in the lab- 

 oratory, having only one window, which was on the west side 

 of the house. During the day the larva moved rapidly away 

 from the light, and when it had reached the end of the roll the 

 table was turned end for end and the insect began traveling 

 in the opposite direction. Although there were forty yards 

 of paper on this roll, it was necessary at 1 p. M. to remove the 

 larva and substitute a fresh roll, as it had crossed the paper 

 from end to end five or six times. 



The complete record of the travel of this larva required 11 

 rolls of paper and one assistant and sometimes two, depend- 

 ing on the activity of the insect, had to be constantly at work. 

 (Fig. 1.) The experiment was carried through continuously 

 until the larva died, and the extraordinary vitality which it 

 exhibited, promised, at one time, to exhaust the supply of assist- 

 ants that could be spared for the work. 



The following table gives the data secured from the record 

 on each roll. 



The larva remained alive from 8:30 Saturday morning 

 until 8 :45 Tuesday morning, 72 hours, and was active the greater 

 part of the time. It was necessary to place the insect in a glass 

 each time a new roll of paper was attached, so that the entire 

 length of time that the larva was actually on the paper was about 

 70 hours. The table gives the distance traveled during differ- 

 ent periods, the total amounting the 9,058 feet, or 1.71 miles. 



