What is "tales de circumstantibus"

Tales \Ta"les\, n. [L., pl. of talis such (persons).] (Law)

1. pl. Persons added to a jury, commonly from those in or about the courthouse, to make up any deficiency in the number of jurors regularly summoned, being like, or such as, the latter.
   --Blount. Blackstone.

2. syntactically sing. The writ by which such persons are summoned.

   Tales book, a book containing the names of such as are admitted of the tales.
   --Blount.
   --Craig.

   Tales de circumstantibus [L.], such, or the like, from those standing about.