Fitted sheet construction

A fitted, adjustable water bed sheet, comprising:

• a substantially rectangular fabric having a top sleeping panel, four depending side panels, and a substantially square, three sided aperture at each sheet corner forming substantially perpendicular edges between the ends of adjacent side panels so that the adjacent ends of the side panels are spaced apart to form a partially open corner when the sheet top panel and side panels are positioned over the water bed mattress top and side surfaces respectively, each of said corners having a stitched dart about two to six inches in length beginning at said aperture and extending inwardly towards the sheet top panel at an angle which substantially bisects the angle between the adjacent sheet side panel edges, whereby partially closed, stitched sheet corners are formed between adjacent sheet side panels to allow the lower portion of each water bed mattress corner to protrude through one of said apertures for unrestricted movement while the stitched portion of each sheet corner lies smoothly over the top of the respective mattress corner when the sheet top sleeping panel and four side panels are positioned to cover the upper surface and four side surfaces of the mattress respectively;
• an elongated flap attached to the lower edge of a first one of said side panels adjacent each stitched corner, each flap extending substantially parallel to the longitudinal axis of each of said first side panels and extending towards the adjacent second side panel when said flap is folded under said mattress, the free end of each flap being adapted to overlie a portion of said adjacent second side panel after said flap has been folded under the respective mattress corner;
• and,
• attachment means mounted on opposed faces of the overlying portions of each of said flaps and second side panels, said attachment means being adapted to removably secure each of said flaps in various positions on said respective second side panels when said flaps are brought into overlying relationship with the respective second side panels, whereby each sheet corner is maintained in position on the respective mattress corner by said sheet side panels and said flaps bearing against the mattress side and lower surfaces.