The Collaborative International Dictionary of English v.0.48:

Presidial \Pre*sid"i*al\, Presidiary \Pre*sid"i*a*ry\, a. [L.
   praesidialis and praesidiarius, fr. praesidium a presiding
   over, defense, guard. See Preside.]
   Of or pertaining to a garrison; having a garrison.
   [1913 Webster]

         There are three presidial castles in this city.
                                                  --Howell.
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Presidiary \Pre*sid"i*a*ry\, n. [L. praesidiarium.]
   A guard. [Obs.] "Heavenly presidiaries." --Bp. Hall.
   [1913 Webster]