One of the most unique of my experiments I made in Central Park, in the autumn of 1891. I secured a very fine phonograph record of the food sound of the Rhesus monkeys belonging to the Park. During the following night there arrived at the Park a shipment of Rhesus monkeys, just from their home in the east of Asia. There were seven of these new monkeys, three adult females and four babies, one of whom was left an orphan by the death of its mother in her passage across the ocean. At my request the superintendent had these monkeys stored in the vacant room in the upper story of the Old Armoury building. They had never seen the monkeys in Central Park, nor had they ever been brought near enough to the monkey-house for them to learn by any means that any other monkeys were about. About sunrise I repaired to this room, where I had my phonograph placed in order, and I enjoined those who were present, by special permission, not to do anything to attract the attention of the monkeys, nor under any condition to show them any food or anything to drink. Having arranged my phonograph, I delivered to them the sounds contained on my cylinder which I had recorded on the day preceding. Up to this time not a sound had been uttered by any inmate of the shipping cage. The instant my phonograph began to reproduce the record, the seven new monkeys began to answer vociferously. After having delivered this record to them, I gave them time to become quiet again. I showed them some carrots and apples, on seeing which they began to utter the same sounds which they had uttered before, and this time I secured a good record of their sounds to compare with the others. [Sidenote: RHESUS MONKEYS] The alarm-sound as given by the Rhesus is very energetic, but not so shrill nor sharp as that of the Capuchin, nor have I discovered more than one such sound. As they are not of a high order of intelligence, nor kindly disposed unless kept in fear, I have not given them a great amount of study, but their sounds come more closely to the range of the human voice than do the sounds of the Cebus, which I regard as the Caucasian of monkeys. The Rhesus is not very intelligent, but when reared in captivity appears to be capable of some degree of domestication. The adult reared in a wild state shows many phases of vicious and uncongenial temper. When well cared for, they are rather hardy and undergo training quite well. They are not a handsome animal, being of a faded tan colour on the back, merged into a yellowish white on the less exposed parts. They have large cheek-pouches which, when not filled with food, allow the skin on the neck and jaws to hang in folds, which give them an appearance of extreme emaciation, and when full of food they are so distended as to present rather an unpleasant aspect.