At the moment of crossing the equator towards the north the sun is said to be at the first point of Aries; some thirty days later it enters Taurus, and so on through Gemini, Cancer, Leo, Virgo, Libra, Scorpio, Sagittarius, Capricornus, Aquarius and Pisces.
The zodiacal Virgo is held to represent the Assyrian Venus, Ishtar, the ruling divinity of the sixth month, and Sagittarius the archer-god Nergal, to whom the ninth month was dedicated.
Sagittarius, figured later as a Centaur, stood for the Babylonian Mars.
A Serpent was the Egyptian equivalent of Scorpio; the Arrow only of Sagittarius was retained; Capricornus became " Life," or a Mirror as an image of life; Aquarius survived as Water; Taurus, Virgo and Pisces remained unchanged.'
Thus, the second sign (of the Ox) occupies the position of Capricorn, the third that of Sagittarius, and so on.
Reminiscences of the Greek signs of Gemini, Leo, Libra, Sagittarius, Capricornus and Pisces are obvious severally in the Hindu Two Faces, Lion's Tail, Beam of a Balance, Arrow, Gazelle's Head (figured as a marine nondescript) and Fish.
To the first six books Gregory subsequently added chapters on the bishops Salonius and Sagittarius, and on his quarrels with Felix of Nantes.