Book - Human Embryology and Morphology (1921)

Human Embryology and Morphology by

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HUMAN EMBRYOLOGY AND MORPHOLOGY

BY

ARTHUR KEITH

M.D., F.R.S., LL.D. (Aberdeen), F.R.C.S. (Eng.)

CONSERVATOR OF THE MUSEUM AND HUNTERIAN PROFESSOR

ROYAL COLLEGE OF SURGEONS, ENGLAND

FDLLERIAN PROFESSOR IN COMPARATIVK ANATOMY, ROYAL INSTITUTION, LONDON

FOURTH EDITION, REVISED AND ENLARGED WITE NEARLY 500 ILLUSTRATIONS

NEW YORK

LONGMANS, GREEN & CO.

LONDON: EDWARD ARNOLD

1921

PREFACE TO FOURTH EDITION

The issue of a new edition has given the author an opportunity not only of incorporating recent additions to our knowledge of the development and morphology of the human body, but also of- recasting many of the chapters. Over eighty new illustrations have been added. The chief alterations relate to sections dealing with the origin of the foetal membranes, the growth of the embryo and foetus, and the nature of the basal ganglia of the brain. The chapters dealing with the pharynx, the ear, the heart, and the lymphatic system have been rearranged and to a large extent rewritten. The enquiries of the late Professor Franklin P. Mall have shown that human embryos, in their earlier stages, are a week older than was formerly believed. The estimated ages of embryos now given in this work are based on Professor Mall's calculations.

Experience has confirmed the author in his earlier opinion that the facts of embryology are barren and meaningless until they are interpreted in the light of our knowledge of the evolution of the human body — a knowledge which must be founded on a comx^rehensive survey of comparative anatomy and physiology. Hence in this new edition the author has sought to give, not only a descriptive history of the development of the various systems of the body, but to make the facts intelligible by bringing a knowledge of comparative anatomy and evolution to bear on them.

Human Embryology and Comparative Anatomy have become vast fields of knowledge. Here they are dealt with only in so far as they bear directly on the nature of the human body, and reflect what the author has found to be useful in the course of his daily work and teaching. Every effort has been made to make the book representative of the latest British Research.

In the preparation of the present edition the author has become indebted to a very wide circle of friends too numerous to be mentioned individually. He cannot, however, allow the occasion to pass without a warm acknowledgment of his indebtedness to Dr. Alexander Low-, Lecturer on Embryology in the University of Aberdeen, for the help he has given.

ARTHUR KEITH.

Royal College oe Surgeons of England,

Lincoln's-Inn-Fields, W.C. 2, 3Iay, 1921.

CONTENTS

CHAPTER PACK

I. Eably Changes in the Development of the Ovum and Embryo

II. The Manner in which a Connection is Established between THE Foetus and Uterus

III. The Primitive Streak, Notochord and Somites

IV. The Age Changes in the Embryo and Eoetus V. The Spinal Column and Back

VI. The Segmentation of the Body

VII. Central Nervous System — Differentiation of the Spinal Cord

VIII. The Mid- and Hind-Brains

IX. The Fore-Brain or Prosencephalon

X. The Fore-Bbain OR Prosencephalon (co«<("«??erZ). Cerebral Vesicles ---------- m

XI. The Cranium XII. Development of the Face -

XIII. The Teeth and Apparatus of Mastication

XIV. The Nasal Cavities and Olfactory Structures

XV. Development of the Structures concerned in the Sense OF Sight

XVI. The Organ of Hearing

XVII. Pharynx and Neck

XVIII. Tongue, Thyroid and Structures developed from the

Walls of the Primitive Pharynx

XIX. Organs of Digestion

XX. Circulatory System

XXII. Respiratory System

XXIII. Urogenital System

XXV. Body Wall and Pelvic Floor

XXVI. Development and Differentiation of the Limb Buds

XXVII. Morphology of the Limbs

XXVIII. Skin and its Appendages