TRIAL AND ERROR REACTIONS IN MAMMALS 53 



TABLE 5 



Distribution of Classified Reactions According To Age and 



Phyletic Averages 



Total Distribution of classified reactions 



classified in percentages of same. 



Average reac- TypeA TypeB TypeC TypeD TypeE 



Subjects. age. tions. % % % % % 



Older human (8) 14 years 226 76.11 19.47 2.21 1.77 0.44 



ManA(l) 45 years 29 48.28 51.72 0.00 0.00 0.00 



BoyA(l) 11 years 40 62.50 7.50 30.00 0.00 0.00 



Infant (1) 26 months 38 15.79 5.26 18.42 26.32 34.21 



Mature monkeys (2) 10 years 75 21.33 22.67 20.00 29.33 6.67 



Immature monkeys (2).... 1.5 years 71 15.49 22.53 30.99 18.31 12.68 



Mature dogs (2) 2 years 82 12.20 21.95 0.00 34.15 31.71 



Older puppies (6) 98.50 days 357 13.61 19.84 14.79 17.51 34.24 



Younger puppies (8) 52.75 days 364 14.26 10.16 13.74 23.08 38.76 



Mature cats (3) 1 year 127 8.66 19.68 3.94 27.56 40.16 



Kittens (2) 63 days 104 6.73 10.58 0.00 14.42 68.27 



Horse (1) 8 years 50 8.00 4.00 2.00 24.00 62.00 



Discussion of table 5. The significance of the findings of the 

 table becomes more apparent when they are plotted in dis- 

 tribution curves, as shown in figure 3 on the opposite page. 

 Reference to these curves will disclose the following facts con- 

 cerning the general effects of age and phyletic position on mode 

 of adjustment: 



(i) The curve for the older human subjects attains its greatest 

 height at point A, whence it descends rapidly to point B, thence 

 to point C, where it closely approximates the base (zero) line. 

 From C to D to E the curve descends continuously. 



(2) The infant's curve is relatively low at point A, whence 

 it descends abruptly to point B, after which it ascends contin- 

 uously and rather sharply imtil it reaches its maximum height 

 at E. 



(3) Defective Man A's curve ascends from A to B; from B 

 it descends directly to the base line, with which it is coincident 

 at points C, D and E. 



(4) Defective Boy A's curve descends sharply from A to B, 

 undergoes a marked secondary rise at C, and from there passes 

 to the base line, with which it is coincident at D and E. 



(5) The mature monkey's curve ascends slightly from A to 

 B; descends slightly from B to C; attains its maximum height 

 at D, from which point it descends sharply to E, where it is 

 near the base line. 



