Oceanographer Cerullo provides a potpourri of odd facts about 25 sea creatures, including lionfish, giant octopus, jellies, stingrays, and tiger sharks. While many of the full-color underwater photos are appealing, the busy format detracts. Each double-page spread includes several paragraphs of text against a brightly colored background, photos, and banal cartoon-like line drawings. Photos cropped and dropped into the layout in a variety of boxes and bubbles offer no information on the size of creatures shown, so the reader is not sure whether the sea snake is larger than a moray eel, or whether a grouper is actually four times the size of a human diver. The author concludes with “helpful hints.” If you get injured exploring the ocean, for instance, she suggests calling “a doctor or poison control center.” Hardly earth-shattering. (glossary, further reading, Web sites, index) (Nonfiction. 8-10)