Milton Levine’s Eureka moment came in 1956, when he spotted a mound of ants during a Fourth of July picnic at his sister’s poolside in Southern California.

Recalling how as a boy he had collected ants in jars at his uncle’s farm in Pennsylvania, he told his brother-in-law and business partner, E. J. Cossman, “We should make an antarium.”

The resulting product  Uncle Milton’s Ant Farm  has been a staple in children’s bedrooms ever since. It offers a bucolic panorama of a farmhouse beside a winding path to a barn and windmill above a warren of ant tunnels, all encased in plastic. More than 20 million have been sold.

Mr. Levine died Jan. 16 in Thousand Oaks, Calif., his son, Steven, said. He was 97.

Selling for $1.98, the original 6-by-9-inch ant farm was an immediate hit, soon selling thousands a week by mail order to children persuaded by commercials on after-school television shows. They were entranced by the idea of staring at Pogonomyrmex californicus  red ants from California  digging those tunnels in boxed-in sand.