Ambarvalia

Ambarvalia was a Roman agricultural fertility rite held at the end of May in honor of Ceres. At these festivals they sacrificed a bull, a sow, and a sheep, which, before the sacrifice, were led in procession thrice around the fields; whence the feast is supposed to have taken its name, ambio, I go round, and arvum, field. This sacrifice was called...
Found on http://en.wikipedia.org/wiki/Ambarvalia

Ambarvalia

Ambarvalia (ămburvāl'yu) , in Roman religion, yearly agricultural rite held at the end of May. To insure fertility and disperse evil, each farmer led members of his household and a sacrificial beast in a procession around the boundaries of his fields.
Found on http://www.infoplease.com/ce6/society/A0803623.html
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