Wu (Fish Faces, 1993, etc.) describes the special world of the coral reef by day and night. An inviting text highlights the author's firsthand diving experiences, but the many full-color underwater photographs--sometimes four or more to a page--are so small they lose impact. The brief captions give the common names of the subjects but not the scientific names, locales, and size. The spider crab, octopus, and squirrelfish appear in photos of similar size that will leave viewers unable to determine the sizes of these creatures in nature. The design is fussy: The photos have been cropped into overlapping silhouettes, ovals, circles, squares, and rectangles of every size, from full-page bleeds to those only slightly larger than postage stamps; lines of text fall across shadowy, worm-like forms tinted pink, blue, or gold. While colorful, Wu's book--without an index--is not as useful as Cerullo's Coral Reef: A City that Never Sleeps (1996). She has a more compelling narrative, employs larger, more arresting photos, and provides further reading and an index.