3. If animals have acetabula in the uterus, these acetabula always become smaller as the fœtus grows, and at last disappear. The umbilical cord is a covering for veins, of which the origin is in the uterus. In those creatures which have acetabula it originates in them; in those that have not acetabula it originates in the vein. In the larger animals, such as the fœtus of oxen, there are four veins; in smaller animals, two; in very small animals, as in birds, there is but one. Two veins reach the fœtus through the liver, from that part called the gates of the liver, towards the great vein; and two go to the aorta, where it is divided into two parts; and there are membranes round each pair of veins, and the umbilical cord surrounds these membranes like a covering. As the fœtus increases, these veins diminish. The embryo, as it grows, advances into the viscera, where its movements are manifest. Sometimes it remains rolled up near the pudendum. CHAPTER VIII. 1. When the pains of parturition come on, they extend to many and various parts of the body, but especially to one or other of the thighs. Those who suffer most in the bowels are delivered most rapidly; those who suffer much in the loins are delivered with difficulty; those whose pain lies in the subumbilical region, more quickly. If the child is a male, a liquid, serum-like discharge, of a pale yellow colour, precedes; if a female, this discharge is sanguineous, but still fluid. Some women have neither during the period of parturition. 2. In other animals parturition is not painful, and it is evident that they suffer but moderately in the pains of labour. In women the pains of parturition are more violent, especially in those that are inactive or that are not well made in their sides, and are unable to hold their breath. They also suffer more in parturition, if they breathe in the meantime, compelled by the necessity of respiration. At first a fluid escapes when the fœtus comes to the birth, and the membranes are ruptured; after this, the embryo is excluded, the uterus being turned, and the uterus being turned inside-out. CHAPTER IX. 1. The division of the umbilical cord often requires the careful attention of the midwife; for by skilfulness she may not only assist in difficult labours, but should attend carefully to the circumstances, and apply the ligature to the umbilical cord of the child; for if the secundines fall out with the child, the umbilical cord must be bound with a ligature of worsted, and cut above the ligature, and where it is bound it joins together, and that which is joined with it falls off. If the ligature becomes loose, the child dies from loss of blood. If the secundines do not come out at once, while they remain within, and the child is outside, the umbilical cord must be tied and divided.