In Roman mythology, Summanus was the god of nocturnal thunder, as opposed to Jupiter, the god of diurnal (daylight) thunder. His precise nature was unknown even to Ovid : "quisquis's est, Summano templa feruntur" ("The temple's said to have been dedicated to Summanus, whoever he may be"). Summanus' temple stood at the Circus Maximus, and every June 20th cakes were offered to him as propitiation. His name can be derived from the Latin sub-manus (cf. mane, Matuta) for "preceding the morning". Tho… (More on Summanus)