Indeed the fishermen may not even join in dance and song with the other men of the clubhouse in the evening; they must keep to themselves and be silent. In Mirzapur, when the seed of the silkworm is brought into the house, the Kol or Bhuiyar puts it in a place which has been carefully plastered with holy cowdung to bring good luck. From that time the owner must be careful to avoid ceremonial impurity. He must give up cohabitation with his wife; he may not sleep on a bed, nor shave himself, nor cut his nails, nor anoint himself with oil, nor eat food cooked with butter, nor tell lies, nor do anything else that he deems wrong. He vows to Singarmati Devi that, if the worms are duly born, he will make her an offering. When the cocoons open and the worms appear, he assembles the women of the house and they sing the same song as at the birth of a baby, and red lead is smeared on the parting of the hair of all the married women of the neighbourhood. When the worms pair, rejoicings are made as at a marriage. Thus the silkworms are treated as far as possible like human beings. Hence the custom which prohibits the commerce of the sexes while the worms are hatching may be only an extension, by analogy, of the rule which is observed by many races, that the husband may not cohabit with his wife during pregnancy and lactation. In the island of Nias the hunters sometimes dig pits, cover them lightly over with twigs, grass, and leaves, and then drive the game into them. While they are engaged in digging the pits, they have to observe a number of taboos. They may not spit, or the game would turn back in disgust from the pits. They may not laugh, or the sides of the pit would fall in. They may eat no salt, prepare no fodder for swine, and in the pit they may not scratch themselves, for if they did, the earth would be loosened and would collapse. And the night after digging the pit they may have no intercourse with a woman, or all their labour would be in vain. This practice of observing strict chastity as a condition of success in hunting and fishing is very common among rude races; and the instances of it which have been cited render it probable that the rule is always based on a superstition rather than on a consideration of the temporary weakness which a breach of the custom may entail on the hunter or fisherman. In general it appears to be supposed that the evil effect of incontinence is not so much that it weakens him, as that, for some reason or other, it offends the animals, who in consequence will not suffer themselves to be caught. A Carrier Indian of British Columbia used to separate from his wife for a full month before he set traps for bears, and during this time he might not drink from the same vessel as his wife, but had to use a special cup made of birch bark. The neglect of these precautions would cause the game to escape after it had been snared. But when he was about to snare martens, the period of continence was cut down to ten days.