In Greek mythology, Linus is the infant son of Apollo and Psamathe, daughter of King Crotopus of Argos. Exposed by his mother and torn apart by sheepdogs, his death brings Apollo's vengeance — plague or the monster Poine — upon Argos until the child and mother are propitiated. Distinct from Linus the Theban/Orphic musician (linus-orpheus).
Adapted from Wikipedia, "Linus (mythology)" and "Psamathe (daughter of Crotopus)" · CC BY-SA 4.0
I.Exposed child of Apollo
Psamathe, fearing her father Crotopus, exposes the newborn Apollo sired. In Conon's telling a shepherd rears the boy until dogs tear him apart; Crotopus then has Psamathe killed, and Apollo sends plague until Argos honors mother and child. Pausanias has the king's own sheepdogs destroy the exposed infant.
Apollo's punishment takes the form of plague or of Poine (Punishment), a child-stealing daemon slain by the Argive Coroebus — whose expiatory wandering founds Tripodiscus near Megara.
II.Not the musician Linus
A far better-known Linus is the lyric master, brother or peer of Orpheus and music teacher of Heracles (atlas linus-orpheus). Argive tomb claims sometimes blur the infant with that singer, but the Crotopid story is a separate local aetiology of plague and child-hero rites.
The id linus-psamathe isolates Apollo and Psamathe's exposed son.