Page "Horoscope" Paragraph 25

It is worth pointing out that the sidereal signs and the tropical signs are both geometrical conventions of 30 ° each, whereas the zodiacal constellations are pictorial representations of mythological figures projected onto the celestial sphere based on patterns of visible star groupings, none of which occupy precisely 30 ° of the ecliptic.

So constellations and signs are not the same, although for historical reasons they might have the same names.