38 



Experiment 5750, Coal-tar. — March 15, at 3:50 p m., a small 

 amount of coal-tar was placed at the center of a nest under the orange 

 cover. The ants began to leave the nest at once, but only gradually. 

 In an hour and forty minutes all were out of the nest except about a 

 dozen which remained with the larvae, seven-eighths of an inch from 

 the tar. Half an hour later the ants were carrying these larvae outside. 

 By the following morning at 8: 30 (16 hours, 40 minutes), about fifty 

 ants were in one corner of the nest, distant five-eighths of an inch 

 from the repellent, and this condition remained unchanged thru this 

 day. Twenty-four hours later about a fourth of the ants were in the 

 nest, but during this day they began to withdraw again, and by 8 a. m. 

 of March 18 all were out of the nest but two, which with a few of 

 the larvae were one and a fourth inches from the tar, the other larvae 

 being outside on the base. By 1.30 of this day these larvae had all 

 been removed, and there was no further change until 8: 30 of the 19th 

 (3 days, 16 hours), when the ants began to return, about half of them 

 being in the nest a fourth of an inch or more from the tar by 11 : 50 of 

 that day. Two days later, six days from the beginning of the experi- 

 ment, about half the ants were under the cover, together with the 

 Lrvae. 



Experiment 5743, Apterite. — March 5, at 11:35 a. m., apterite 

 moistened with water was placed at the center of a nest. The ants 

 were at first not very strongly repelled, but soon began to carry their 





L^t-yae ■ 



Fig. 16 



larvae towards the edge of the nest. By 3 : 15 all the workers were out- 

 side the nest except four, which were at one corner. Half of the 



