As among the Mexicans, the Maya years were related to the points of the compass. The later Yucatec associated kan-years with the east, muluc-years with the north, ix-years with the west and cauac-years with the south, but the relation of the earlier year-bearers is not clear, owing to the uncertainty which attaches to the glyphs expressing the world-directions. On this point the evidence is very conflicting, but I am inclined to think that most probably they are as shown in Fig. 57. The doubt lies between east and west on the one hand and between north and south on the other. The world-directions evidently possessed much ritual importance among the Maya, though not perhaps so much as among the Mexicans. In the creation myth in one of the books of Chilan Balam we read of the establishment of four trees at the four quarters, and one at the centre, a legend which recalls the five trees with their respective birds shown in the Mexican codex Borgia and allied manuscripts (Fig. 10; p. 79). The “crosses” at Palenque, each of which is surmounted by a bird, probably also had reference to two of the world-directions, in any case their resemblance to the trees of the Borgia codex is striking. The four Bacabs who supported the heavens north, south, east and west, have already been mentioned, and also the four cross-roads on the way to Xibalba. Four colours are associated with the last, and these are the colours which the later Yucatec associated with the points of the compass, viz. yellow (kan) with the east, red (chac) with the north, white (zac) with the west, and black (ek) with the south (Fig. 57). The manuscripts however do not always show the colours in association with the same direction-signs. The colour assigned to the year appears in one of the series of names assigned to the Bacab which was supposed to be its regent. Thus Hobnil, regent of the kan-years, is called Kanal Bacab, Kanzicnal of the muluc-years, Chacal Bacab, Zaczini of the ix-years, Zacal Bacab, and Hozanek of the cauac-years, Ekel Bacab. The Maya did not limit their calculations to the computation only of the solar calendar, but also reckoned the synodical revolutions of the planet Venus (584 days). Certain pages of the Dresden codex are devoted to this purpose, and the glyph representing the planet is thus known. Some investigators have tried to prove that the reappearances of other planets, Mars, Mercury, Jupiter and Saturn, were also computed, but the evidence is unsatisfactory, and even in many cases adverse to the supposition.