TENTACLES

Subtitled ``The Amazing World of Octopus, Squid, and Their Relatives,'' a fascinating introduction to the cephalapods, which also include the nautilus and cuttlefish. Martin first discusses the creatures' general characteristics and place in the animal kingdom, then goes on to specific discussions of each, sampling subjects like their variety (there are 375 species of squid), place in the food chain, mating habits, range, and remarkable adaptations. Like the best of teachers, his text is enthusiastic but scrupulously scientific, well informed but never dry—he has a gift for colorful description and slips in some delightful anecdotes: the octopus's ``intelligence, curiosity, and fluidity make them escape experts,'' and he reports one making its way as far as a library, where it was found ``pulling down books and paging through them.'' Splendid color photos, amply supplied, and informative drawings round out an unusually attractive and informative offering. Glossary; index. (Nonfiction. 7-12)