In the ever-expanding field of heart research the needs of established re searchers, students and general readers can vary considerably, making it difficult therefore to cater for all types of audience within a single volume. The aim of this book has been to provide a comprehensive and up-to-date review of the structure of the heart, including its cell biology. The ultrastructure of the working myocardium and all portions of the conduction system, together with their development, is covered in detail. Also included are chapters on the morphometry of cardiac muscle, the innervation of the heart, cardiac hyper trophy and regeneration, and the development of the coronary circulation. A detailed review of cardiac muscle in cell culture is also provided. It is to be hoped that readers, whatever their background, will find the information contained herein useful for their needs. This work was supported by a grant from the National Heart Foundation of Australia. The authors wish to gratefully acknowledge the following people for their invaluable assistance in preparation of the manuscript: Professor Yasuo Uehara, D'r. Takashi* Fujiwara, Dr. Peter Baluk, Dr. Seiji Matsuda and Bill Kaegi for providing unpublished micrographs; Fabian Bowers, Patricia Murphy and Janet Bennett for typing; and Lucy Popadynec, Nella Puglisi, Maggie Mackie, Mary Delafield and Liana Butera for assistance with references and figure preparation. THE AUTHORS Contents A. General Introduction 1 Morphology of Cardiac Muscle 8 B.