for a microinjection of liquids or suspensions of substances into living cells , a stage and a cannula , which is movably mounted and extends at an oblique angle relative to the stage , are arranged to be movable relative to each other , the cells being contained in a culture vessel on the stage , the tip of the cannula constitutes a pointer and is moved in a plane z 1 , which is parallel to the stage and is disposed above the cells on the stage , the tip is moved to a position exactly over the location which is desired for an injection and thereafter , the cannula is moved away from the selected cell in the direction of the projection of the cannula on the plane and over a distance which depends on the angle between the cannula and the plane , the cannula is thus moved to a setback position , in which the axis of the cannula extends through the desired location , the cannula is then axially moved to puncture the cell and is subsequently reversed .