Volume 1
On the anatomy, physiology, and pathology of the chimpanzee / by Charles F. Sonntag.
- Sonntag, Charles F. (Charles Frederick), -1925
- Date:
- 1923
Licence: In copyright
Credit: On the anatomy, physiology, and pathology of the chimpanzee / by Charles F. Sonntag. Source: Wellcome Collection.
103/118 page 423
![very large pisiform bone. The trapezium, on the other hand, is small, and there is no os centrale as in Simia, The minute . flexor longus pollicis is an offshoot of the tendon of the flexor profundus to the index. The palmaris brevis is large, the first and second lumbricales are connected by a muscular slip, and there are six palmar interossei. Still those anatomical differences are not sufficient to show that the hand of the Chimpanzee is not such a marvellous mechanism as that of Man. The muscles of the abdominal parietes are very strong, for they act as flexors of the trunk, and they support the abdominal viscera when the animal is walking. A pelvic floor is present, but there is no true central point of the perineum, which plays such an important part in supporting the uterus in woman. The vulva and anus are behind a line connecting the anterior extremities of the ischial tuberosities, but a corresponding line ki woman passes between the vulva and anus. The quadratus lumborum is shorter than in Man, and is strongly fused with the iliacus, and the latter is longer than in Man. The glutei are less than those in Man, but the maximus has a longer insertion. The glutei and other thigh muscles exhibit a considerable degree of adhesion, and some of the thigh muscles are inserted into the fascia over the muscles of the leg. The scansorius is absent in Man. The adductors form a powerful mass, and they help to keep the inverted foot against a tree in climbing; from the backward projection of the ischium the adductor magnus is a powerful extensor of the leg in leaping. In the muscles of the leg it is interesting to note the doubling of the tibialis anticus and the absence of a tibial head of the soleus. Anatomical literature contains many speculations as to the nature of the foot of the Chimpanzee. Cuvier, Blumenbach, and Owen, and in later years Huxley (27), Humphry (26), and Embleton (19) have proposed different views. A surve}^ of their writings shows that it has been regarded as a foot, a hand, or a compromise between them, that is a chiropodous structure. To settle this question it is necessary to consider the extremities from the anatomical and physiological points of view, and it is necessary to examine them in several animals. Using the human hand as a standard, it is, in the first place, necessary to see how it differs from a fore-foot. Humphry (26) points out that the elongation of the phalanges and the shortness and opposability of the pollex are the characters which transform a fore-foot into a hand. In the case of the terminal part of the lower extremity many of the myological and osseous features are characteristic, not of a hand or a foot, but of a, hind limb. So we must look to the characters of the digits and hallux to determine the nature of the part in the Chimpanzee. Comparing the measurements in [ioi]](https://iiif.wellcomecollection.org/image/b2982123x_0001_0103.jp2/full/800%2C/0/default.jpg)
