. "18 is a plan view of the device of FIG. 17; FIG. 19 is a cross sectional view of another surgical device of the invention; FIG. 20 is a plan view of the device of FIG. 19; FIG. 21 is a cross sectional view of a further surgical device of the invention; FIG. 22 is a cross sectional view of a still further surgical device of the invention; FIG. 23 is plan view of the device of FIG. 22; FIG. 24 is a" . . .