| OCR Text |
Show 298 DR. A. KEITH ON THE CHIMPANZEES. [Mar. 7, acquired no degenerate sexual habits. The sexual state, so far as Mr. Mackay has observed, does not change with the season of the year. Of menstruation in the Gorilla, nothing is known. 3. The Relationship of the Chimpanzee to the Gorilla. An examination of all the structural systems of the African Anthropoids leads to the inference that the Gorilla is the more primitive of the two forms, and approaches the common parent anthropoid more nearly than the Chimpanzee. The teeth of the Gorilla, individually and collectively, form a complete dentition, a dentition at the very highest point of development; the teeth of thh Chimpanzee show marked signs of retrogression in development of size and structure. The muscular development and the consequent bony crests for muscular attachment of the Gorilla far surpass those of the Chimpanzee. The muscular development of the adult Chimpanzee represents the system of the adolescent Gorilla. Some of the bodily organs of the Gorilla belong to a simpler and earlier primate type than those of the Chimpanzee. But in one point the Chimpanzee evidently represents more nearly the parent form-its limbs and body are more adapted for arboreal locomotion; of the two, the Gorilla shows the nearer approach to the human manner of locomotion. On the whole, the evidence at our disposal at the present time points to the fact that the Chimpanzee is a Gorilline derivative, in which, with a progressive brain-development, there have been retrograde changes in most of the other parts of the body. The various forms of Chimpanzee differ according to the degree to which these changes have proceeded. 4. The Brain-development in the Chimpanzees and Gorilla. The temperament of the Gorilla and Chimpanzee is absolutely different. All the Gorillas of Avhich we have any knowledge agree in being sullen, untamable, and ferocious, even the youngest of them. They do not tolerate confinement: only one has lived over a year in captivity in Europe ; one is said to have been in the possession of au African chief for six years. The Chimpanzee, on the other hand, at any rate in its younger stages, takes to confinement easily, is teachable and playful. The elaborate toilet and performance gone through daily by " Johanna," the skilful Avay in which she decants her glass of wine, removing and replacing the stopper, declares her to be a Chimpanzee more clearly than any other character she could show. Her education is probably the most elaborate ever possessed by any ape. She appears to be colour-blind. D u Chaillu states that the Chimpanzee to Avhich he gives the name of T. kooloo-kamba had a distinctive cry; from her physical features " Johanna " appears to belong to that species. When in a fit of passion, into which she is easily throAvn, the hair of the scalp becomes erect, she beats the floor Avith her feet and hands, |
