DECEPTIVE APPEARANCES OF INTELLIGENCE 159 
of previous activity I do not pretend to say; but the case is 
cited as an illustration of a possible way in which a certain 
class of habits may be interpreted. 
Habit formation may be shown in the action of individual 
organs of our bodies. The stomach according to the re- 
searches of Pawlow readily acquires habits, and the influence 
of habit in the functioning of the intestines is generally 
familiar. Between such habit formation and the increase 
of an organ through action there is much in common, and 
between these phenomena and the adaptive changes of an 
organ in relation to its condition of stimulation there is 
doubtless a fundamental kinship. What Roux has called 
the “overcompensation of what is used” is a principle which 
probably manifests itself in all these cases. 
DECEPTIVE APPEARANCES OF INTELLIGENCE 
There are a great many cases which have been adduced as 
indicating intelligence and even a simple form of reasoning 
which may be explained like the phenomena we have de-| 
scribed. It is frequently difficult to distinguish acts which | 
are instinctive from those which an animal has learned to| 
perform, and it is well in general to be guided by the prin- | 
ciple enunciated by Lloyd Morgan, which is a sort of special | 
case of the law of parsimony—namely, that “In no case may | | 
we interpret an action as the outcome of the exercise of a 
higher psychical faculty, if it can be interpreted as the out- | 
come of one which stands lower in the psychological scale.” 
One of the cases most suggestive of the power of forming 
associations in the Ccelenterates is recorded by Fleure and 
Walton whose account is as follows: 
“We have given a specimen of Actinia a scrap of filter- 
paper about once in twenty-four, hours, placing it on the 
same tentacles each time. As a general rule the fragment was 
