“At the annual session of the American Scientific Association, held at old Harvard University, the celebrated Professor Agassiz remarked, ‘We find that young animals, of almost all classes, within the egg, differ widely from what they are in their full-grown condition. We find, too, that the young bat, or bird, or the young serpent, in certain periods of their growth, resemble one another so much that we would defy anyone to tell one from the other.’”

Scientific American, September 1849

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