Abstract: A syringe comprises a barrel with a reciprocable piston having a liquid passage between the piston ends. The outer piston end is connectable to a needle, and an open ended tubular sheath having a needle and a handle end, and being slidable over the barrel, and attachable to the piston, to extend around the barrel when the piston is toward the handle end of the barrel. The piston is selectively detachable from the sheath, and is movable, after such detachment and with retraction of the barrel from the sheath, to selectively draw a needle means attached to the piston into the sheath.