FIG. 1 shows a top perspective view of an ornamental design for an irrigation basin;
FIG. 2 shows an additional perspective view of the irrigation basin of FIG. 1, wherein the broken lines showing suction tubing and a hand are for contextual purposes only;
FIG. 3 shows a further perspective view of the irrigation basin of FIG. 1, wherein broken lines showing suction tubing and an arm are for contextual purposes only;
FIG. 4 shows a further perspective view of the irrigation basin of FIG. 1, wherein broken lines showing suction tubing and a foot are for contextual purposes only;
FIG. 5 shows a further perspective view of the irrigation basin of FIG. 1, wherein broken lines showing suction tubing and a leg are for contextual purposes only;
FIG. 6 shows a bottom perspective view of the irrigation basin of FIG. 1;
FIG. 7 shows a rear elevation view of the irrigation basin of FIG. 1;
FIG. 8 shows a front elevation view of the irrigation basin of FIG. 1;
FIG. 9 shows a top plan view of the irrigation basin of FIG. 1;
FIG. 10 shows a bottom plan view of the irrigation basin of FIG. 1;
FIG. 11 shows a right side elevation view of the irrigation basin of FIG. 1; and,
FIG. 12 shows a left side elevation view of the irrigation basin of FIG. 1.
The features shown in broken lines depict environmental structure in the drawings, and do not form part of the design sought to be patented.