“Has every seed got a little plant inside it, Uncle George?” Dolly asked.

“Every seed, Dolly, no matter how small.”

Uncle George split up one of the hard seeds that had not been soaked, and showed them a little plant of the same kind inside; but it was so hard and brittle that he could crumble it up into powder between his fingers.

“And what are the two large white lobes for?” asked Frank.

“These are the seed-leaves. They are stores of plant-food. The young plant is fed by these until its root grows far down into the soil and its shoot grows high up into the air—until it is old enough and strong enough to find food for itself, in fact.

“In the bud, the little shoot is fed by the sap of the mother-plant. Here, in the seed, we have a baby plant wrapped up in two coats, one thick and leathery and the other soft and warm; and, in place of a large feeding-bottle, there are two huge masses of plant-food wrapped up with it.”

“Why do we put seeds in the ground to make them grow?” asked Frank.

“A seed requires three things to make it grow. These three things are—water, air, and warmth. We can grow seeds without soil at all if we give them these three things. But if either water, air, or warmth be wanting, your seeds cannot grow.”

“That is why seeds won’t grow outside in winter, then,” said Frank.

“That is the reason,” his uncle answered. “In winter there is not enough heat to make seeds grow. If you sow seeds in a pot of dry soil in summer, and do not give them water, they will not grow.”