8. Some kinds of food check the milk, as the medic grass, especially in ruminating animals. The cytisus and orobus have a very different effect; but the flower of the cytisus is unwholesome, and causes inflammation; the orobus does not agree with pregnant cattle, for it causes difficulty of parturition. On the whole, those animals which are able to eat the most food, as they are better adapted for parturition, will also give the most milk, if they have enough food. Some of the flatulent kinds of food, when given to animals, increase the quantity of milk, as beans given freely to the sheep, goat, ox, and chimœra,[97] for they cause the udder to be distended; and it is a sign that there will be plenty of milk when the udder is seen below before parturition. [97] Some kind of domestic goat, but not known. 9. The milk lasts a long time in those that have it, if they remain without sexual intercourse, and have proper food; and in sheep it lasts longer than in any other animals, for the sheep may be milked for eight months. Altogether the ruminating animals produce milk in greater abundance, and more fitted for making cheese. Around Torona the cows fail in their milk a few days before calving, but give milk all the rest of the time. In women dark-coloured milk is better for the children than that which is white; and black women are better nurses than white women. The most nutritious milk is that which contains the most cheese, but that which contains less cheese is better for infants. CHAPTER XVII. 1. All sanguineous animals eject the spermatic fluid; the office it performs in generation, and how it is performed, will be treated of in another place. In proportion to his size man ejects more than other animals. This fluid, in animals covered with hair, is glutinous, in others it is not glutinous; in all it is white, so that Herodotus is mistaken when he says that the Ethiopians have black semen.[98] The semen comes out white and thick if it is healthy, but after ejection it becomes thin and black; it does not thicken with cold, but becomes thin and watery, both in colour and density. By heat it coagulates and thickens, and when it has been ejected for any time into the uterus, it comes out more thick, and sometimes dry and twisted together. That which is fruitful sinks in water, but the barren mixes with it. All that Ctesias said about the semen of the elephant is false. [98] Herodotus, iii. c. 97, 101. BOOK THE FOURTH. CHAPTER I.