Robigalia
Robigo (Latin Robigus) is the Roman god of wheat rust, a disease of wheat caused by a fungus. This divinity was considered masculine by the oldest authors (Varro, Verrio Flacco and its epitomator Festus) that speak of a god Robigus, whereas during the imperial age it was considered like a goddess since authors like Ovidio and Columella and the Christians Tertullian, Lactancio and San AguistÃn speak of a goddess Robigo ("Robigine"). Probably, the change was due to match the gender of the divinity with the common name Robigo, which in Latin is feminine and indicates rust.
Its festival, denominated Robigalia, was celebrated the 25 of April, in the period in which the ears begin to form. Ovid described in the fourth book of the Fasts [1] the ceremony of the Robigalia: a procession of people all dressed in white, guided by the Priest of the Quirinal (flamine quirinale), that goes to the sacred forest of the god in the fifth mile (fifth miglio) of the Clodia road (the current sixth mile of Via Cassia) and here the priest sacrificed a dog and a suckling lamb (ie, two years old). Also racing competitions were developed. It is assumed that due to the gender change of the divinity the gender of the victims has also been changed, so a small dog and a lamb originally had to be sacrificed. The reason for the canine sacrifice is explained by the Priest himself to Ovid: when the "Dog's Star" (ie, Sirius) appears in the sky the warm (caniculous) season begins and there is a risk that the fruits mature too early; to avoid this risk a dog (or bitch) is sacrificed by its analogy with the name of the constellation. In fact it is probable that the dog was sacrificed by its condition of animal related to infernal divinities like Robigo. Notes
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