According to the Homeric Hymn to Hermes, Zeus in the dead of night secretly begot Hermes upon Maia, who avoided the company of the gods, in a cave of Cyllene. After giving birth to the baby, Maia wrapped him in blankets and went to sleep. The rapidly maturing infant Hermes crawled away to Thessaly, where by nightfall of his first day he stole some of his brother Apollo's cattle and invented the lyre from a tortoise shell. Maia refused to believe Apollo when he claimed Hermes was the thief and Zeus then sided with Apollo. Finally, Apollo exchanged the cattle for the lyre, which became one of his identifying attributes.
Maia also raised the infant Arcas, the child of Callisto with Zeus. Wronged by the love affair, Zeus's wife Hera in a jealous rage had transformed Callisto into a bear. Arcas is the eponym of Arcadia, where Maia was born. The story of Callisto and Arcas, like that of the Pleiades, is an aition for a star formation, the constellations Ursa Major and Ursa Minor, the Great and Little Bear.
Her name is related to μαῖα (maia), an honorific term for older women related to μήτηρ (mētēr) 'mother'.Maia also means "midwife" in Greek.
Mercury and Maia inside a silver cup dedicated by the freedman P. Aelius Eutychus (late 2nd century AD), from a Gallo-Roman religious site
In an archaic Roman prayer, Maia appears as an attribute of Vulcan, in an invocational list of male deities paired with female abstractions representing some aspect of their functionality. She was explicitly identified with Earth (Terra, the Roman counterpart of Gaia) and the Good Goddess (Bona Dea) in at least one tradition. Her identity became theologically intertwined also with the goddesses Fauna, Magna Mater ("Great Goddess", referring to the Roman form of Cybele but also a cult title for Maia), Ops, Juno, and Carna, as discussed at some length by the lateantiquarian writer Macrobius. This treatment was probably influenced by the 1st-century BC scholar Varro, who tended to resolve a great number of goddesses into one original "Terra." The association with Juno, whose Etruscan counterpart was Uni, is suggested again by the inscription Uni Mae on the Piacenza Liver.
The month of May (Latin Maius) was supposedly named for Maia, though ancient etymologists also connected it to the maiores, "ancestors," again from the adjective maius, maior, meaning those who are "greater" in terms of generational precedence. On the first day of May, the Lares Praestites were honored as protectors of the city, and the flamen of Vulcan sacrificed a pregnant sow to Maia, a customary offering to an earth goddess that reiterates the link between Vulcan and Maia in the archaic prayer formula. In Roman myth, Mercury (Hermes), the son of Maia, was the father of the twin Lares, a genealogy that sheds light on the collocation of ceremonies on the May Kalends. On May 15, the Ides, Mercury was honored as a patron of merchants and increaser of profit (through an etymological connection with merx, merces, "goods, merchandise"), another possible connection with Maia his mother as a goddess who promoted growth.
Genealogy of the Olympians in Greek mythology
^Vivian Nutton, Ancient Medicine (Routledge, 2004), p. 101.
^Although the identification of Mercury is secure, based on the presence of the caduceus, the one-shouldered garment called the chlamys, and his winged head, the female figure has been identified variously. The cup is part of the Berthouville Treasure, found within a Gallo-Roman temple precinct; see Lise Vogel, The Column of Antoninus Pius, Loeb Classical Library Monograph (Harvard University Press, 1973), pp. 79–80, and Martin Henig, Religion in Roman Britain, (Taylor & Francis, 1984, 2005), pp. 119–120. In Gaul, Mercury's regular consort is one of the Celtic goddesses, usually Rosmerta. The etymology of Rosmerta's name as "Great Provider" suggests a theology compatible with that of Maia "the Great". The consort on the cup has also been identified as Venus by M. Chabouillet, Catalogue général et raisonné des camées et pierres gravées de la Bibliothéque Impériale (Paris, 1858), p. 449. Maia is suggested by the concomitant discovery of a silver bust, not always considered part of the hoard proper but more securely identified as Maia and connected to Rosmerta; see E. Babelon, Revue archéologique 24 (1914) 182–190, as summarized in American Journal of Archaeology 19 (1915), p. 485.
^Robert Turcan, The Gods of Ancient Rome: Religion in Everyday Life from Archaic to Imperial Times (Routledge, 2001), p. 70.
^Pierre Grimal, The Dictionary of Classical Mythology (Blackwell, 1996, originally published in French 1951), p. 270.
^In Mario Torelli's diagram of this haruspicial object, the names Uni and Mae appear together in a cell on the edge of the liver; see Nancy Thompson de Grummond, Etruscan Myth, Sacred History, and Legend (University of Pennsylvania Museum of Archaeology, 2006), p. 44 online.
^Ovid, Fasti v.73; Turcan, The Gods of Ancient Rome, p. 70.