6o8 LIFE : OUTLINES OF GENERAL BIOLOGY 



lessen during the period of observation the number of subsequent 

 failures. It is profitable to contrast this case with the way in which 

 an untaught thrush, carefully observed by Miss Frances Pitt, 

 learned to opt^n its first wood-snail. In the course of a week it passed 

 through the stages of indifference, interest, fumbling strokes, more 

 effective thrusts, lifting the shell, and finally hammering it on a 

 stone until it broke. But when it reached the solution which it had 

 deliberately sought, it did not require any further experimenting. 

 It had learned its lesson — along an intelligent line. 



The term "habit" should be restricted to the individual cnTegistra.- 

 tion of a novel sequence of actions, which require to be in some way 

 "learned". In the sequence established, one neuromuscular action 

 automatically calls up another, and that another, and so on; and 

 it is easier that the Hnks in the chain should follow one another 

 than that anything else should happen. As people often use the 

 words "habit" and "habits" with other quite different meanings, 

 we keep the term habituation for the individually acquired enregis- 

 tration, as well as for the process by which the enregistering is 

 effected. There are two important points: (a) to distinguish habitua- 

 tion, which requires to be individually "learned", from instinctive 

 capacities and reflex actions, which form part of the inherited 

 organisation; and {b) to recognise that the habituation may be 

 effected by non-intelligent as well as by intelligent repetitions of the 

 same experience. 



The difficulty of grading the different kinds of "learning" is 

 illustrated by the ability many animals show in mastering a maze or 

 labyrinth. This is often made like a miniature of Hampton Court's, 

 and the animal is bribed to attention by a reward placed in the 

 centre or at the doorway, according as the pupil learns to work in 

 or out, or both ways. The maze can be mastered by monkeys, rats, 

 mice, guinea-pigs, pigeons, tortoises, and so on; but wherein the 

 process of "learning" precisely consists remains doubtful. Experi- 

 ments have been varied so as to exclude the assistance of the senses 

 of smell and sight; there is probably a memory of muscular move- 

 ments. In a few days a docile rat will become quite familiar with 

 the maze, and will scamper through it without blundering or even 

 hesitating. After an interval of several weeks without any further 

 maze-exixrience, a well- trained rat will run through the labyrinth 

 without making any mistake, so that here again there is enregistra- 

 tion. A man might discern the particular rule or secret of the maze 

 and keep that in mind; or a man might possibly form a mental 

 picture of the perplexing paths; but we may be sure that what the 

 rat does is something very different — something more physiological 

 and less psychological. The probability is that it has a "kinesthetic 

 sens<'" that enables it to remember the effective routine of move- 

 ments. It must l)e noticed that these maze-solving creatures do not 



