Four of them appeared in the song 'The Twelve Days of Christmas
' except they didn't really. Although 'Calling Birds' is to be seen most commonly now, originally they were 'Colly Birds'. "What," you might well ask, "is a 'colly' bird?" Well, it's a blackbird. Colly is an old word derived from coal
, specifically refering to the dust.
So now you know.