I have caught one sound from the spider monkey by which I have been able to attract the attention of others of the same species, but I am as yet uncertain about its meaning. I do not believe that it has any reference to food; but I think perhaps it is a term of friendship, or a sound of endearment. One reason for this belief is, that I have heard it used on several occasions when a monkey of this kind would see its image in a mirror. I have used the sound in Washington, Philadelphia, and Atlanta, and induced the monkey addressed to respond to it and come to me. I almost concluded at one time that this species was nearly dumb, until I saw one enraged by a green monkey that occupied an adjoining cage. On this occasion she raised her voice to an extremely high pitch, and uttered a sound having great volume and significance. This she repeated several times, and it was the first time I had ever seen a spider monkey show any sign of resentment. On another occasion, where this same specimen saw a brilliant peacock near the window by her cage, the sounds which she made at that strange object were loud, clear, and varied. I have read with surprise an account of a spider monkey which Dr. Gardner had with him in his travels through South America. He describes it as the most intelligent of all monkeys, but I cannot believe that his experience with monkeys was sufficient to rank him as an authority on that subject. I do not pretend, however, to know all that there is to be known concerning this species, but so far as my study of them goes they scarcely laugh, cry, or show any sign of emotion. They do not usually resent anything; thus they are harmless and timid. Their long, lean, half-clad limbs look like the ghost of poverty, and their slow, cautious movements like decrepitude begging alms. They would be objects of pity if they only had sense enough to know how Nature has slighted them. [Sidenote: "JESS"] I have recently received a letter from Mr. A. E. McCall, of Bath, New York, enclosing a photograph of a monkey of this kind, by the name of "Jess." The gentleman tells me that he has been giving some time to the study of the actions and language of this monkey, and assures me that it is very docile, and follows him like a dog, and kindly offers to make such experiments with it as I may suggest, by which to aid me in the pursuit of my own researches, and I shall take advantage of his kind offer. I am aware that there are exceptions to all rules, and I am not disposed to deprive the spider monkey of the place he may deserve in the scale of Simian life by reason of his intellect or speech; but as this book is a record of what I know, and not what I have heard of, I shall for the present be compelled to place the spider monkey very far down in the scale of intellect and speech.