Ideas:

I have already proposed that we should read this glyph and the identical glyph in Monday as 'measurement staff', a ruler determining periods of time. The periods of Venus seem to have been 'manipulated' by the Maya Indians. They have not chosen to map the observed times, but instead mapped somewhat different periods:

  observed periods periods in the Mayan 'map' difference
morning star 263 236 - 27
black 50 90 + 40
evening star 263 250 - 13
black 8 8 0
sum 584 584 0

In Skywatchers Aveni explains these differences as due to efforts to coordinate the movements of Venus with those of the Moon.