The head singer, called ke´ kai tca (C) and ke´ūya (E), was a man of great importance in ceremonies, though he was very inconspicuous. It was his duty to plan previously the proper sequence of the dances and songs, and it was also his duty to start all songs and to carry the air. The head singer had to possess a very good voice, and had to make it his business to know the songs for the various ceremonies. Now and then he was at a loss for the proper song for a particular occasion. He was allowed to consult some other singer, or, upon occasion, he might ask for suggestions from the audience. Any one who knew a song which fitted the occasion might come to the head singer and sing it for him in an undertone, until he caught it and was ready to lead in the singing. As a rule he kept time with a split-stick rattle, or a rattle made of cocoons. The chorus or burden-singers, called skam (E), gave volume to the music and marked time with their split-stick rattles, hai mitamitaka (N). Their usual burden was "he, he, he, he, ..." sung in a heavy monotone. The drummers, called tsīlo´ gaūk (E), tsīlo´ tca (C), and tsīlo´ matūtsī (E), were always two in number, and as a rule they took turns in playing the large wooden drum which was set in the ground at the rear of the dance-house, and which was beaten by the stamping of the feet. The office of drummer was considered one of the most important, and second only to that of fire-tender. The master of ceremonies, called xabē´ dima (E), xabē´gaūk (E), and he´līma (C), started and stopped all songs and dances by certain signals. The participants in the dance usually maintained certain positions, but the master of ceremonies ran about from place to place supervising the activities and giving directions as required. His presence was absolutely necessary at all ceremonies, and without him a dance could not proceed. He acted under the general direction of the head captain, but that official himself never served as master of ceremonies. Very rarely did the same individual serve as master of ceremonies and head singer. While as a rule the drummers and the singers wore no special dress for ceremonial occasions, the masters of ceremonies were almost always painted and dressed according to different requirements for each ceremony (see below). They were usually among the dancers who impersonated supernatural beings. GENERAL FEATURES OF POMO CEREMONIES A ceremony always centered about the dance-house,[5] and lasted four nights, or some multiple of four, beginning usually soon after sunset. In the case of the "ghost ceremony," which began at sunrise, the preceding night was spent in performing other dances. Such ceremonies were made up of a varying number of dances. There was usually no prescribed sequence, but the ceremony took the name of the dance which was its special feature, though this need not necessarily open the ceremony. In a few instances it was recognized that certain dances should be performed together.