This is the fourth title in the publisher's Step-Up Series which is designed to be a little more challenging than a beginning book in terms of vocabulary. What the authors do with their slightly more difficult words is play on the native interest children of all ages bring to the world's strangest animals. The information given on bats' radar, gorilla tantrums, whale digestion etc. is of the most glancing limited sort. The art is of the Sunday comic supplement variety for draftsmanship and color.