"I wonder what they are," said Happy Jack. "They don't grow, for they haven't any roots. They are not thorns, for there is no plant from which they could come. They are not alive, so what can they be?" Now, Happy Jack's eyes are bright, but sometimes he doesn't use them to the very best advantage. He was so busy examining the queer things on the ground that he never once thought to look up in the tops of the trees.