An extraordinary amount of information is packed into the pages of this new First Book, and the high standard set by this series is once more sustained. The approach is very direct; the child's initial interest is assumed (witness the crowds that visit the displays of fossil reptiles and amphibians in natural history museums); and the immensities of time spans as animals evolved over millions of years is dramatized by not only an illuminating text but by the exquisitely decorative and accurately informative drawings by Helene Carter. Use this as a step to Carroll Fenton and Herbert Zim in an increasingly popular field of interest.