Designed for quick and easy reference, this is a study of more than 200 of the weird and wonderful creatures - some of them only recently discovered - that roamed the earth long ago. The text is concise, and is supported by fact-boxes alongside each illustration to highlight key points. Also included are a pronunciation guide, and silhouettes to show relative sizes. The author is a palaeontologist who has written other books on dinosaurs, having travelled the world on fieldwork and research.