The Mental Life of Monkeys and Apes | Page 3

of his data
(Hamilton, 1911, 1914). In his most recent paper on "A study of sexual
tendencies in monkeys and baboons," he has given important
information concerning several of the monkeys which I have observed.
For the convenience of readers who may make use of both his reports
and mine, I am designating the animals by the names previously given
them by Hamilton. The available and essential information concerning
the individuals is presented below.

List of animals in collection Skirrl. Pithecus irus. Adult male.
Sobke. _P. rhesus_. Young adult male.
Gertie. _P. irus-rhesus_. Female. Born November, 1910.
Maud. _P. rhesus_. Young adult female.
Jimmy II. _P. irus_. Adult male.
Scotty. _P. irus_ (?). Adult male.
Tiny. _P. irus-rhesus_. Female. Born August, 1913.
Chatters. _P. irus_. Adult eunuch.
Daddy. _P. irus_. Adult eunuch.
Mutt. _P. irus_. Young adult male. Born August, 1911.
Julius. Pongo pygmaeus. Male. Age, 4 years to 5 years.

When I arrived in Santa Barbara, Doctor Hamilton was about to
remodel, or rather reconstruct, his animal cages and laboratory. This
gave us opportunity to adapt both to the special needs of my
experiments. The laboratory was finally located and built in a grove of
live oaks. From the front it is well shown by figure 10 of plate III, and
from the rear, by figure 11. Its location was in every way satisfactory
for my work, and in addition, the spot proved a delightful one in which
to spend one's time.
[Illustration: FIGURE 12.--Ground plan of Montecito laboratory and
cages. Scale 1/120
L, laboratory; C, cages; A, experiment room in which multiple-choice
apparatus was installed; B, E, additional rooms for research; D, store
room and shop; Z, large central cage communicating with the eight
smaller cages 1-8.]
Figure 12 is a ground plan, drawn to scale, of the laboratory and the
adjoining cages, showing the relations of the several rooms of the

laboratory among themselves and to the nine cages. Although the
construction was throughout simple, everything was convenient and so
planned as to expedite my experimental work. The large room A,
adjoining the cages, was used exclusively for an experimental study of
ideational behavior by means of my recently devised multiple-choice
method. Additional, and supplementary, experiments were conducted
in the large cage Z. Room D served as a store-room and work-shop.
The laboratory was forty feet long, twenty-two feet wide, and ten feet
to the plate. Each small cage was six, by six, by twelve feet deep, while
the large compartment into which each of the smaller cages opened was
twenty-four feet long, ten feet wide, and twelve feet deep.

II
OBSERVATIONAL PROBLEMS AND METHODS
My chief observational task in Montecito was the study of ideational
behavior, or of such adaptive behavior in monkeys and apes as
corresponds to the ideational behavior of man. It was my plan to
determine, so far as possible in the time at my disposal, the existence or
absence of ideas and the rôle which they play in the solution of
problems by monkeys and apes. I had in mind the behavioristic form of
the perennial questions: Do these animals think, do they reason, and if
so, what is the nature of these processes as indicated by the
characteristics of their adaptive behavior?
My work, although obviously preliminary and incomplete, differs from
most of the previous studies of the complex behavior of the infrahuman
primates in that I relied chiefly upon a specially devised method and
applied it systematically over a period of several months. The work was
intensive and quantitative instead of more or less incidental, casual, and
qualitative as has usually been the case. Naturally, during the course of
my special study of ideational behavior observations were made
relative to various other aspects of the life of my subjects. Such, for
example, are my notes on the use of the hands, the instincts, the
emotions, and the natural aptitudes of individuals. It is, indeed,
impossible to observe any of the primates without noting most
interesting and illuminating activities. And although the major portion
of my time was spent in hard and monotonous work with my
experimental apparatus, I found time each day to get into intimate

touch with the free activities of my subjects and to observe their social
relations and varied expressions of individuality. As a result of my
close acquaintance with this band of primates, I feel more keenly than
ever before the necessity of taking into account, in connection with all
experimental analyses of behavior, the temperamental characteristics,
experience, and affective peculiarities of individuals.
The light which I have obtained on the general problem of ideation has
come, first, through a method which I have rather inaptly named the
multiple-choice method, and second, and more incidentally, through a
variety of supplementary methods which are described in