Turner, Homing of Ants. 429 



12. Do. 8:05a.m. Same apparatus as above, only a dark chamber opening upon stage and incline 

 was placed over the top of the incline. One set of workers conveyed pupae to the dark chamber; another 

 set, stragglers from the nest, conveyed them from the dark chamber to the nest. The delay represents 

 the time that elapsed before a straggler from the nest discovered the pupae in the dark chamber. The 

 ants had rested nine minutes. 



13. July 16, 7:39 a.m. Same as above. The workers had rested two days, twenty-one hours and 

 fifty-nine minutes. 



14. Do. 2:07 p.m. Same apparatus as above. The delay was caused because they stored all of 

 the pupae in the dark chamber before any were carried into the nest. The ants had rested four hours 

 and a half. 



Fig. 7. Learning-curve of an individual Formica fusca var. subsericca Say, showing lapse of mem- 

 ory, etc. 



Apparatus. Two cardboard stages, I and 2; inclines D and E leading to the island from each, respec- 

 tively. The feet of the inclines were side by side. Each was attached to the right side of the stage. 

 The marked worker was placed on stage 2 (see p. 412). 



A. On trips 6 and 7 the pupa was taken from stage I to the nest. 



B. On trip 12, do. 



C. The worker ascends and descends incline D, then ascends and descends incline E, then ascends 

 to stage 2 and carries a pupa to the nest. 



D. On trip 36 the pupa was taken from stage i. 



E. On trips 43-45, do. 



F. On trip 50, do. 



