Behavior of Monkeys and Apes HTML version

of absence from Harvard. This invitation I most gladly accepted,
and in February, 1915, I established myself in Santa Barbara, in
convenient proximity to Doctor Hamilton's private laboratory
where for more than six months I was able to work uninterruptedly
under nearly ideal conditions.
Doctor Hamilton without reserve placed at my disposal his entire
collection of animals, laboratory, and equipment, provided
innumerable conveniences for my work, and in addition, bore the
entire expense of my investigation. I cannot adequately thank him
for his kindness nor make satisfactory acknowledgment here of his
generous aid. Thanks to his sympathetic interest and to the
courtesy of the McCormick family on whose estate the laboratory
was located, my work was done under wholly delightful
conditions, and with assistance from Ramon Jimenez and Frank
Van Den Bergh, Jr., which was invaluable. The former aided me
most intelligently in the care of the animals and the construction of
apparatus; and the latter, especially, was of very real service in
connection with many of my experiments.
The collection of animals which Doctor Hamilton placed at my
disposal consisted of ten monkeys and one orang utan. The
monkeys represented either Pithecus rhesus Audebert (Macacus
rhesus), Pithecus irus F. Cuvier (Macacus cynomolgos), or the
hybrid of these two species (Elliot, 1913). There were two
eunuchs, five males, and three females. All were thoroughly
acclimated, having lived in Montecito either from birth or for
several years. The orang utan was a young specimen of Pongo
pygmaeus Hoppius obtained from a San Francisco dealer in
October, 1914 for my use. His age at that time, as judged by his
size and the presence of milk teeth, was not more than five years.
So far as I could discover, he was a perfectly normal, healthy, and
active individual. On June 10, 1915, his weight was thirty-four
pounds, his height thirty-two inches, and his chest girt twenty-three
inches. On August 18 of the same year, the three measurements