Originally published in 1933, this book is a culmination of a lifetime of research by Hans Friedrich Gadow into the evolution of the vertebrae. Gadow outlines the various forms of vertebral development as a guide to larger and more general questions on the morphological scheme of the evolution of vertebrate creatures, and uses plentiful diagrams, photographs and reconstructions to trace spinal development. This book will be of value to anyone with an interest in the history of science.