A beautiful book -- with illustrations using about half of every page,-in line on one side, in full color -- pastel -- on the other. The text is an imaginative journey through the ages of animal development, from the time the first signs of life showed in the mud, up to man. Bobby's uncle was a scientist, head of a Natural History Museum, and sometimes he used words too difficult for Bobby. But Boyd Smith's pictures make it all very credible, and any small boy or girl who is fascinated by the models and fossils in the Museum will find this absorbingly interesting and feel that it makes more sense than more exact ways of telling the story. It should be shared with a grown-up first; then the pictures can be a game of recognition, with the line drawings a key to the colored illustrations.