From Smith's Dictionary of Greek and Roman Biography and Mythology (London, 1880)
ACHELO'IS. 1. A surname of the Sirens, the daughters of Achelous and a muse. (Ov. Met. v. 552, xiv. 87; Apollod. i. 7. § 10.)
2. A general name for water-nymphs, as in Columella (x. 263), where the companions of the Pegasids are called Acheloides.
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