A father had promised his two sons

A father had promised his two young sons he would take them on a fishing trip.

The boys were digging for fishing bait in their parents’ garden.

Uncovering a many legged creature, one of the boys proudly dangled it before his Father.

“No, son, he won’t do for bait,” his Father said.

“He’s not an earthworm.”

“He’s not?” the boy asked, his eyes wide.

“What planet is he from?”