Castalides
Could not find Castalidum in Logeion dictionaries. Looking for closest alphabetic form.
Casta'lides
(Κασταλίδες), the Castalian nymphs, by which the Muses are sometimes designated, as the Castalian spring was sacred to them. (Theocrit. 7.148; Martial, 7.11.) [L.S]