Whenever the Tarahumares make pinole while away from home, they sacrifice the first part to the water-serpents, dropping it with the little stick with which the pinole is stirred.  They sprinkle it first forward, then to the left, then to the right, and then upward, three times in each direction.  If they did not do this, the water-serpents would try to catch them and chase them back to their own land.  Besides the sacrifice of the fish ball, they offer axes, hats, blankets, girdles, pouches, etc., and especially knives and strings of beads, to the master of the fish, who is considered to be the oldest fish.  This is in payment for what they are going to catch, and the donations are either hung to a cross or a horizontal bar specially erected in the middle of the river, and remain hanging there until daybreak, when their respective owners take them back.

In the meantime eight or ten men have gathered the amole and soke.  They wrap the plants in their blankets and bring them direct to the river, where they are to be used.  The leaves are pounded with stones and spread out for a while before sunset.  As soon as it is dark the men throw them into the water, and trample on them to make the juice come out.  Three or four men take turns, standing waist-deep in the water, treading with all their might and howling.  The effect of the poison in the course of the night is said to reach down some 300 yards.  It stupefies the fish, and although many of them revive, a few are killed and may be eaten, as the poison does not affect the meat.

The managers see to it that everybody does his duty and that no one falls asleep during the night, while the women help by watching the mats, that the otters may not eat the fish caught in them.

A curious detail is that one man on each side of the river is deputed to heat stones and throw them into the river three or four at a time, every half-hour, possibly to frighten off the serpent.  During the night not one fish is taken up, but at daybreak the managers go down the river to investigate the effect of the poison, and upon their return the fish are gathered in, the men often diving into deep water for them.  The work is done with great earnestness and almost in silence, the women helping the men in catching the fish.  While. the fishing is going on they do not eat any of the fish, for fear of not getting more, but during the day quantities are broiled and eaten, without salt or chile, however, and the bones are invariably thrown into the fire.  Most of the fish are cut open in the back and placed on rocks or on trees to dry for future use.  Such fishing may last for two days and nights, and is finished by dancing yumari and drinking maguey wine.  On one occasion as much was caught as ten men could carry.  Expeditions of this kind may be repeated two or three times a year; but when food is plentiful a whole year may pass without one being undertaken.