"The Laily Worm and the Machrel of the Sea" (Roud 3968, Child 36) is an English-language folk song.
[2] A young man, transformed into a laily (loathly, or loathsome) worm, tells his story: his father married an evil woman as his stepmother, and she transformed him into a worm and his sister into a mackerel.
This ballad has motifs in common with "The Laidly Worm of Spindleston Heugh", "Kemp Owyne", and more with "Allison Gross", but is an independent one, and a traditional one, unretouched by literary forms.
[3] The sister can comb the hair in "Allison Gross" because she still has her human form; Francis James Child believed that part of the original tale has been lost, in which she could assume her human form again for part of the week.
[4] The horn has a logical plot function in this tale, unlike "Allison Gross".