Читать книгу Woman - William J. Robinson - Страница 12

The internal sex organs are situated in the lower part of the abdominal cavity, the part that is called the pelvis, or pelvic cavity. The meaning of the word pelvis in Latin is basin. The pelvis, also referred to as the pelvic girdle or pelvic arch, forms a bony basin, and is composed of three powerful bones: the sacrum, consisting of five vertebræ fused together and constituting the solid part of the spine, or vertebral column, in the back, and the two hipbones, one on each side. The two hipbones meet in front, forming the pubic arch.

The hipbones are called in Latin the ossa innominata (nameless bones) and each hipbone is composed of three bones: the ilium, the ischium, and the os pubis. The thighs are attached to the hipbones, and to the hipbones are also attached the large gluteal muscles, which form the buttocks, or the "seat."

The pelvis of the female differs considerably from the pelvis of the male. The female pelvis is shallower and wider, less massive, the margins of the bones are more widely separated, thus giving greater prominence to the hips; the sacrum is shorter and less curved, and the pubic arch is wider and more rounded. All this is necessary in order to permit the child's head to pass through. If the female pelvis were exactly like the male pelvis, a full-term living child could never pass through it. The two illustrations show the differences between the male and female pelvis very clearly.

Note particularly the differences in the pubic arches: in the male pelvis it is really more of an angle than an arch. Also note how much longer and more solid the sacrum (with its attached bone, called the coccyx[2]) is in the male pelvis. The differences in the pelves (the plural of pelvis is pelves) of the male and female become fully marked at puberty, but they are present as early as the fourth month of intra-uterine life.