[Illustration: Clam and oyster shells]
"What are you going to do with all these shells?" he asked Periwinkle.
"Do with them?" laughed Periwinkle. "Why, nothing. We threw them away. They show what good things we have had to eat, do they not, Foam?"
Foam was a girl with white teeth.
"Yes," said Foam, laughing. "They are shells of oysters and clams and periwinkles that we have eaten."
"Um-m! what lots of them you have eaten!" said Thorn, looking over the big pile.
"Yes," said Periwinkle, with a laugh, "we live on them."
"But you see," Foam went on, "our people have lived here for a long time—longer than my grandfather can remember. And the shell mounds have been growing all that time. There are many other shell heaps all along this shore, where more of our people live."
Thorn looked down to the water's edge and saw men pulling hollow logs down to the shore.