In Canto Two of his poem John Shade (the poet in VN's novel Pale Fire, 1962) describes the paring of his fingernails and compares his thumb to the grocer's son:
The little scissors I am holding are
A dazzling synthesis of sun and star.
I stand before the window and I pare
My fingernails and vaguely am aware
Of certain flinching likenesses: the thumb,
Our grocer's son; the index, lean and glum
College astronomer Starover Blue;
The middle fellow, a tall priest I knew;
The feminine fourth finger, an old flirt;