Lewis & Short

Eumolpus, i, m., = Εὔμολπος, a fabulous Thracian singer and priest of Ceres, who brought the Eleusinian mysteries and the culture of the vine to Attica, Plin. 7, 56, 57, § 199.
His descendant of the same name, the son of Musaeus, Ov. M. 11, 93.
A sacerdotal family in Athens also bore, after him, the name Eumolpĭdae, ārum, m., Εὐμολπίδαι, Cic. Leg. 2, 14, 35; Nep. Alc. 4 al.