"river nymphs, ycleped of old the Napaeae, or the Naiades, in the vulgar tongue translated into oyster-wenches"

Hylas and the Nymphs
Public DomainHylas and the Nymphs - Credit: Francesco Furini, 1635
In Greek mythology the Napaeae are a type of nymph that live in wooded valleys, glens or grottos, while the Naiades nymphs presided over fountains, wells, springs, streams, and brooks.  They were often the object of archaic local cults, worshipped as essential to humans.

Ycleped is an archaic term for ‘named’ or ‘called.’