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THE
ORIGIN OF VERTEBRATES
BY
WALTER HOLBROOK GASKELL
M.A., M.D. (CANTAB.), LL.D. (EDIN. AND McGILL UNIV.); F.R.S.; FELLOW OF TRINITY
HALL AND UNIVERSITY LECTURER IN PHYSIOLOGY, CAMBRIDGE; HONORARY FELLOW
OF THE ROYAL MEDICAL AND CHIRURGICAL SOCIETY; CORRESPONDING MEMBER
OF THE IMPERIAL MILITARY ACADEMY OF MEDICINE, ST. PETERSBURG, ETC.
LONGMANS, GREEN, AND CO.
39 PATERNOSTER ROW, LONDON
NEW YORK, BOMBAY, AND CALCUTTA
1908
All rights reserved
CONTENTS
| PAGE | |
| Introduction | 1 |
| CHAPTER I | |
| The Evidence of the Central Nervous System | |
| Theories of the origin of vertebrates—Importance of the central nervous system—Evolution of tissues—Evidence of Palæontology—Reasons for choosing Ammocœtes rather than Amphioxus for the investigation of this problem—Importance of larval forms—Comparison of the vertebrate and arthropod central nervous systems—Antagonism between cephalization and alimentation—Life-history of lamprey, not a degenerate animal—Brain of Ammocœtes compared with brain of arthropod—Summary | 8 |
| CHAPTER II | |
| The Evidence of the Organs of Vision | |
| Different kinds of eye—Simple and compound retinas—Upright and inverted retinas—Median eyes—Median or pineal eyes of Ammocœtes and their optic ganglia—Comparison with other median eyes—Lateral eyes of vertebrates compared with lateral eyes of crustaceans—Peculiarities of the lateral eye of the lamprey—Meaning of the optic diverticula—Evolution of vertebrate eyes—Summary | 68 |
| CHAPTER III | |
| The Evidence of the Skeleton | |
| The bony and cartilaginous skeleton considered, not the notochord—Nature of the earliest cartilaginous skeleton—The mesosomatic skeleton of Ammocœtes; its topographical arrangement, its structure, its origin in muco-cartilage—The ... BU KİTABI OKUMAK İÇİN ÜYE OLUN VEYA GİRİŞ YAPIN!Sitemize Üyelik ÜCRETSİZDİR! | |