Which type of creature did Corrie befriend at Scheveningen?

Corrie befriended an ant.

And I was not alone much longer: into my solitary cell came a small, busy black ant. I had almost put my foot where he was one morning as I carried my bucket to the door when I realized the honor being done me. I crouched down and admired the marvelous design of legs and body. I apologized for my size and promised I would not so thoughtlessly stride about again.

After a while he disappeared through a crack in the floor. But when my evening piece of bread appeared on the door shelf, I scattered some crumbs and to my joy he popped out almost at once. He picked up a heroic piece, struggled down the hole with it, and came back for more. It was the beginning of a relationship.