The ornamental design for an octagonalballcourt, as shown and described.
FIG. 1 is a perspective view looking into the room at one wall of the
octagonal ball court of my design;
FIG. 2 is an elevational view of the exterior of the end wall of the
octagonal ball court of my design, the other exterior end wall being the
same;
FIG. 3 is a left side wall elevation of the octagonal ball court of my
design taken along lines 3--3 of FIG. 2, the right side wall elevation
being a mirror image;
FIG. 4 is a ceiling view of the octagonal ball court of my design taken
along lines 4--4 of FIG. 2; and
FIG. 5 is a floor view of the octagonal ball court of my design taken along
lines 5--5 of FIG. 2. The exterior walls are plane and unornamented.