Cervula

Cervulus or Cervula is the name of a Roman festival celebrated on the kalends of January (1 January). According to Chambers (1864), remnants seem to have been incorporated into a medieval Christian Feast of the Ass,[1] (Festum Asinorum), which honors the role of donkeys in the Bible, including the Flight into Egypt.[2]

References

1. Miles, Clement A. (1912). Christmas in Ritual and Tradition. from Chapter XIII: Masking, the Mummers’ Play, the Feast of Fools, and the Boy Bishop, "Mr. Chambers's theory is that the ass was a descendant of the cervulus or hobby-buck who figures so largely in ecclesiastical condemnations of Kalends customs."
2. "It took place on the kalends of January and was a kind of New Year's festival, at which people exchange strenae (étrennes, 'gifts') dressed up as animals or old women, and danced through the streets singing, the applause of the populace. According to DuCange (s.v. cervulus), sacrilegious songs were sung. This happened even in the vicinity of St. Peter's in Rome" >Jung, C. G. (1968). The archetypes and the collective unconscious. Princeton, N.J: Princeton University Press. pp. 257 fn. 3. ISBN 0-691-01833-2.