The results of the tests appear in Table 15.
No record of the choices in the first two of the 17
series was kept. The totals therefore include
15 series, or 300 tests, with each individual.
Neither the daily records nor the totals of this table
demonstrate choice on the basis of color discrimination.
Either the dancers were not able to tell one box from
the other, or they did not learn to go directly to
the orange box. It might be urged with reason
that there is no sufficiently strong motive for the
avoidance of an incorrect choice. A mistake simply
means a moment’s delay in finding food, and
this is not so serious a matter as stopping to discriminate.
I am inclined, in the light of result of other experiments,
to believe that there is a great deal in this objection
to the method. Reward for a correct choice should
be supplemented by some form of punishment for a mistake.
This conclusion was forced upon me by the results
of these preliminary experiments on color vision and
by my observation of the behavior of the animals in
the apparatus. At the time the above tests were
made I believed that I had demonstrated the inability
of the dancer to distinguish orange from blue, but
now, after two years’ additional work on the
subject, I believe instead that the method was defective.
The next step in the evolution of a method of testing
the dancer’s color vision was the construction
of the apparatus (Figures 14 and 15) which was described
in Chapter VII. In connection with this experiment
box the basis for a new motive was introduced, namely,
the punishment of mistakes by an electric shock.
Colored cardboards, instead of the white, black, or
grays of the brightness tests, were placed in the
electric-boxes.
TABLE 15
ORANGE-BLUE TESTS, WITH FOOD-BOX
MOUSE
A MOUSE B
SERIES DATE
1904
RIGHT WRONG RIGHT WRONG
(ORANGE)
(BLUE) (ORANGE) (BLUE)
