"I am glad that he spoke just as he did," Mrs. Edson smiled, "for he reminds me that frogs are as good an example as I can take next. He belongs to one of the lower classes of animals, not so very much higher than the plants. Now, in the plants, you will remember, it was necessary for the pollen to enter the ovary in order to reach and fertilize the seeds. But with the frog it is not so. The female lays the eggs first, and just as she is doing so the male places himself in such a position towards her that he can mingle his zoosperms with her eggs as they come out. That fertilizes them and they immediately begin to grow. First they become tadpoles, and then little frogs." "What, was Old Croaky ever a little tadpole, mumsey?" "Yes, darling, he was. Every frog was once. And before that he was an egg, one of many, in his mother's ovary, and it is so with all animals. They all of them have eggs and zoosperms, just as the plants have pollen and seeds. Only, with most of the animals, the zoosperms must enter the ovary in order to fertilize the eggs, as is the way of the plants. And it is the same with the birds. They are higher, that is later, in the scale of life than the frogs are. Now the higher the creature the more complicated becomes the process of reproduction, even though the principle is always the same. It is always growth, always the life within, forcing itself out to take form, and it is only the forms that change. The life and force within are the same that the first single cell had." "It is very wonderful, mamma," Elsie said, awed by the mystery, even though she was very far from grasping the whole of it. "And the birds, mamma, have they stamens, and eggs inside? I thought their eggs were outside, in a little nest. And some of them are, mumsey, because, you know, I have seen them lots of times."