Corax

En la mitología griega, un cuervo era servidor de Apolo, y éste lo envió con la copa (constelación de la Copa) a que le trajese agua, pero el cuervo tardó en volver porque estuvo esperando a que madurara un higo cerca del manantial. Trajo la copa y una serpiente de agua entre sus garras y dijo a Apolo que se había retrasado porque la serpiente le había atacado. Apolo, sabiendo que el cuervo mentía, puso a los tres en el cielo: condenó al cuervo a estar sediento siempre, pues aunque la copa está cerca, la serpiente (constelación de la Hidra), no le permite beber.

—https://es.wikipedia.org/wiki/Corvus_(constelación)

In the legend of the bull-slayer the Raven has the role of the messenger who comes to entrust Mithras with his mission. He takes the place, as it were, of Mercury, the messenger of the gods, and bears as his emblem the caduceus, the magic staff of Hermes-Mercury.

On the Ostia a cup has been added, and although in the Santa Prisca version the Raven in the procession of the seven grades has unfortunately been lost, beside its place can still be read the words: Nama Coracibus tutela Mercurii, ’Hail to the Ravens under the protection of Mercury’.

The Raven symbolises the air and at the initiation he must have undergone certain rituals relating to this element, rituals which are called corvina or coracina sacra and which qualify the initiate as a ieros koras or ’divine Raven’. We sometimes find this adjective sanctus used in connection with other grades too, but particularly with the Pater, the Father or head of the community. When attending a service, the Raven wears a raven mask (Fig. 5.).