This, however, is an exception. Where only one month is named from the rising of a star or brought into connexion with it--in this case the stars in question are usually the Pleiades--the latter furnishes the means of correcting the reckoning of the months, and the intercalary month is consequently introduced, as need arises, before the month in question. The Pleiades month therefore of itself becomes the starting-point of the reckoning of the months, i. e. becomes the beginning of the year. Immediately after the discovery of America it was already reported of certain tribes on the Mexican coast that they began the year at the setting of the Pleiades and divided it into moon-months[894]. In Loango the months are counted from new moons, but Sirius, the rainy star, offers a means of correcting the reckoning sidereally. With the first new moon which sees Sirius rising in the east their new cycle of twelve months begins, and this must run as well as it can until the new year. When the cycle of months and the year do not fit, which happens about every three years, a thirteenth month must be inserted. This is the evil time, when the wandering spirits are at their worst[895]. The Caffres have twelve moon-months with the usual descriptive names: on this account uncertainty often arises as to which month it really is. The confusion is always rectified by the morning rising of the Pleiades, and the reckoning goes on smoothly for a time, until the months once more get out of place and it becomes necessary to refer again to the stars in order to correct them[896]. In Bali the Pleiades and Orion are observed for the purpose of correcting the calendar of moons by intercalation: thus the month _kartika_ is doubled, or the month _asada_ is prolonged until the Pleiades appear at sunset. Moreover certain natural phenomena are observed[897]. In New Zealand, where all months were described by stars, the year began with the new moon following on the rising of the winter star _puanga_ (Rigel)[898]; the thirteenth month often passed unobserved[899], i. e. served as an intercalary month. Elsewhere we are told that the displacement of the moon-months in relation to the year was rectified through the observation of the rising of the Pleiades and of Orion, and that the most accurate way of calculating the beginning of the year was to observe the first new moon after the morning rising of Rigel[900]. The Papuans limit the year by the constellation of the Serpent, _manggouanija_; when it appears again in the north, it is a sign that the new year is beginning[901]. The people of Nauru, west of the Gilbert Islands, count by moon-months. The time that elapses until the Great Bear returns to the same spot is reckoned as a year[902]. The last two reports are so condensed that it is impossible to see whether the stars serve for the rectifying of the calendar of moons found among these peoples, or only for the fixing of the beginning of