224 MIND IN EVOLUTION CHAP. 



low to pull efficiently). Fails to find right string ; pulls wrong 

 one ; back, and looks for right, but does not see it till I point 

 repeatedly. 



11. Right first. 



12. Right attempted; misses seizing it. Pulls wrong, chews 

 it, and goes back to right. 



Next day. 



Right five times running. He only pulled at wrong string at 

 beginning, while I was arranging experiment, and before I put 

 right string up. (N.B. wrong string once pulled down after 

 biscuit eaten.) 



In this series ; 



(a) He was right from the first when he saw process of 

 arrangement. 



(b) When not seeing it, his first record was wrong, right, 

 wrong, right, right. 



(c) Then came shortening of string, and he failed to see it. 

 That twice put him wrong. But that he had really learnt the 

 right string is shown by his behaviour next day, when the string 

 was made more easy to see, and he made no mistake. He there- 

 fore certainly learnt to discriminate strings in eight experiments 

 without seeing the biscuit put up ; and probably three trials 

 would have been enough, but for the difficulty of sight. 



I now reversed the strings, making the arrangement before his 

 eyes. We will call the string which was formerly right and now 

 wrong, the old string, and the other the new string. 



1. Pulls the old string first, then new. 



2. New. 



3. New. 



He is now taken away, so that he cannot see biscuit put up. 

 Result : 



I 1 times pulls old string first, each time passing the new string 

 to get to it. 



12. Stops at right, with claw on it ; hesitates, looking towards 

 old ; biscuit falls down. 



13. Old again. After three-quarters of an hour : 



14. Old. 24. Old ; hesitation. 



15. New. 25. Old. 



1 6. Old. 26. New. 



17. Old. 27. New. 



1 8. New. 28. New. 



19. Old. 29. New. 



20. New. 30. New. 



21. Old. 31. New. 



22. Old. Next day. 



23. New. New, five times running. 



