1889.] FACULTIES OF THE BALD CHIMPANZEE. 317 
infancy, and therefore higher than that which is presented by any 
brute, so far at least as I have met with any evidence to show. 
Nevertheless, the only attempts that she makes by way of vocal 
response are three peculiar grunting noises—one indicative of assent 
or affirmation, another (very closely resembling the first) of dissent 
or negation, and the third (quite different from the other two) of 
thanks or recognition of favours. In disposition she is somewhat 
capricious, though on the whole good-humoured, fond of her keepers, 
and apparently never tired of a kind of bantering play which off and 
on they keep up with her continually. By vocalizing in a peculiar 
monotone (imitative of the beginning of her own “song”’), they are 
usually able to excite her into the performance of a remarkable 
series of actions. First she shoots out her lips into the well-known 
tubular forms (depicted in Darwin’s ‘ Expression of the Emotions,’ 
p. 141), while at the same time she sings a strange howling note, 
interrupted at regular intervals: these, however, rapidly become 
shorter and shorter, while the vocalization becomes louder and louder, 
winding up to a climax of shrieks and yells, sometimes accompanied 
with a drumming of the hind feet and a vigorous shaking of the 
network which constitutes her cage. The whole performance ends 
with a few grunts. 
A year or two ago it occurred to me that I might try some psycho- 
logical experiments on the intelligence of this animal. The cireum- 
stances in which she is placed, however, did not prove favourable 
for anything like systematic instruction. Being constantly exposed 
to the gaze of a number of people coming and going, and having 
her attention easily distracted by them, the ape was practically 
available for purposes of tuition only during the early hours of the 
morning, before the menagerie is open to the public; and, as a rule, 
I did not find it convenient to attend at that time. Therefore, the 
results which I am about to describe do not in my opinion represent 
what might fairly have been expected under more favourable condi- 
tions; if the Chimpanzee could have been kept as a domestic pet 
for a few months (as I kept a Cebus kindly lent me for the pur- 
poses of psychological observation by this Society), there can be 
no doubt that many much more interesting results might have been 
obtained. Nevertheless, it appears to me that even those which 
thus far have been obtained are worthy of being placed on record ; 
and although some of them have already been published a few 
months ago in my work on ‘ Mental Evolution in Man,’ since that 
time some further progress has been made; and therefore in the 
present paper I will state together all the facts which have been 
hitherto observed. 
Having enlisted the intelligent cooperation of the keepers, I re- 
quested them to ask the ape repeatedly for one straw, two straws, or 
three straws. Theseshe was to pick up and hand out from among 
the litter in her cage. No constant order was to be observed in 
making these requests, but whenever she handed a number not 
asked for, her offer was to be refused, while if she gave the proper 
number her offer was to be accepted, and she was to receive a piece 
