The co-founder of the company that brought to the world the Frisbee and the Hula Hoop, has died in Southern California. Arthur “Spud´´ Melin of Costa Mesa, who had Alzheimer´s disease, died Friday at age 77. Melin and his boyhood friend Richard Knerr founded Wham-O in 1948 by selling slingshots. In the late 1950´s they began marketing the Frisbee. It was spun off from a Yale student game of tossing pie-tins back and forth. Frisbee sales were eclipsed by another Wham-O game toy, the Hula Hoop, developed from a rattan hoop imported from Australia. Eventually, Wham-O sold 25 million hula hoops.