33 and 39 once the end walls 25 and 26 have been raised perpendicular to bottom wall 22 partial top wall members 27 and 28 can be folded along respective fold lines 49 and 62 so as to become positioned perpendicular to their respective end walls 25 and 28 and substantially parallel to and in partially overlying relationship to bottom wall 22 resting atop the top edges of side walls 23 and 24 and corner support members 32 and 33 and 38 and 39 corner support members 30 35 36 and 41 are then folded downwardly about their respective fold lines 55 58 54 and 59 so that corner support member 30 35 36 and 41 assume positions substantially parallel and in overly outside relationship to respective end portions of side walls 23 and 24 again a suitable adhesive material or other fastening means can be applied during this step so as to affix corner support member 30 35 36 and 41 in place against side walls 23 and 24 the final step in the construction is then the folding of corner support members 31 34 37 and 40 about their respective fold lines 56 57 60 and 61 so.