This classic textbook of invertebrate zoology--used for many years in countries around the world-- has been completely revised in a new edition. It has been made more readable and concise, while incorporating significant research advances made since the last edition was published in 1971. The work surveys all invertebrate phyla, emphasizing those aspects of biology that lend insight into their evolutionary adaptations and phylogeny. Wherever possible, the latest cladistic analyses for the phyla are included to make the book a useful text for graduate students and undergraduates who need to understand the diversity of the animal kingdom. The text has been rewritten and completely reorganized, and now includes the first cladistic analysis of all the invertebrate phyla, as well as newly discovered phyla and classes. Read Less