The Hearse Song

"The Hearse Song" is a song about burial and human decomposition, of unknown origin. It was popular as a World War I song, and was popular in the 20th century as an American and British children's song, continuing to the present. It has many variant titles, lyrics, and melodies, but generally features the line "the worms crawl in, the worms crawl out", and thus is also known as "The Worms Crawl In".

While there are reports of the song dating back to British soldiers in the Crimean War (1853–1856), it certainly dates to at least World War I (1914–1918), when it was sung by American and British soldiers, and was collected in various World War I songbooks of the 1920s. The key line "the worms crawl in, the worms crawl out" appears in some versions of the otherwise unrelated song "There was a lady all skin and bone", and may date to 1810 or earlier.

It gained more popularity in present times by being included Scary Stories to Tell in the Dark (1981) by Alvin Schwartz, who gives the lyrics as:

"Don't you ever laugh as the hearse goes by,
For you may be the next one to die.
They wrap you up in big white sheets
and cover you from head to feet.
They put you in a big black box
And cover you with dirt and rocks.
All goes well for about a week,
Until your coffin begins to leak.
The worms crawl in, the worms crawl out,
The worms play pinochle on your snout,
They eat your eyes, they eat your nose,
They eat the .
A big green worm with rolling eyes
Crawls in your stomach and out your sides.
Your stomach turns a slimy green,
And pus pours out like whipping cream.
You'll spread it on a slice of bread,
And that's what you eat when you are dead."

There are a number of variations in the chorus of this song. In late 1950s eastern Washington state, it was sung:

The worms crawl in, the worms crawl out,
The worms play pinochle on your snout.
A big black bug with two red eyes,
crawls up through your stomach and out through your eyes.
Your liver turns to a slimy green,
And looks and tastes like whipped cream.

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Wikipedia