How right for Young Scott to follow the simple speculative What's Inside? (May Garelick, 1955) with an equally fine photostudy of just what is inside a fertilized egg. Some of the opening pleasantries sound a little silly (""Large, small, or smallest, the marvelous thing about all eggs is that they don't get their babies scrambled"") but the author does have the good sense to dispel an anxiety common to children: ""No chick would ever grow from your kitchen egg because the eggs sold for eating usually come from farms where the rooster is kept away from the hens."" The bulk of the book, however, consists of a day-by-day depiction of a developing chick that begins even before the embryo exists, with chromosome rearrangement, and continues until the chick forces its way out of the shell and, the following day, stands alone. The diary notes significant transitions (when it becomes unmistakably a bird, when it becomes unmistakably a chick), why the order of development is fixed, how the chick is prepared for its emergence into the world, and many other matters that have larger implications. It also pauses to show how the remarkable close-ups of organs, blood vessels and amnion were taken without harming the organism. A twenty-one day wonder indeed, and of quite a different nature from the Cosgrove Eggs and What Happens Inside Them.