or Musets. Gaps in a hedge; places through which a hare makes his way to escape the hounds.
The many musits through the which he goes Are like a labyrinth to amaze his foes.
The passing of the hare through these gaps is termed musing. The word is from musse (old French), a little hole.
Source: Dictionary of Phrase and Fable, E. Cobham Brewer, 1894