Salii were priests of Mars Gradivus, and are said to have been instituted by Numa. They were twelve in number, chosen from the patriarchs, and had charge of the sacred shields (ancilia). which were kept in the Temple of Mars on the Palatine Hill. The distinguishing dress of the salii was an embroidered tunic bound with a brazen belt, the trabea, and the apex, also worn by the flamines. Each had a sword by his side, and in his right hand a spear or staff. The festival of Mars was celebrated by the salii on the 1st of March, and for several successive days, on which occasion they were accustomed to go through the city in their official dress, carrying the ancilia, singing and dancing. The members of the collegium were elected by co-optation. Tullus Hostilius established another collegium of salii. These were twelve in number, were chosen from the patricians, and appear to have been dedicated to the service of Quirinus. They were called the Salii Collini, Agonales, or Agonenses.