CONTENTS 



Page 



Preface vii 



CHAPTER I 



The Position of Cytology in Biological Science 1 



Biology — Cytology — The Classic Period of Cytology — Cytology in the 

 Twentieth Century — What Cytology Is. 



CHAPTER 11 



The Organism and the Cell 11 



The Typical Protoplast — Growth — Differentiation — ('orrelatif>n — Tissues 

 and Organs — Conclusions. 



CHAPTER 111 



The Structural Components of Protoplasts 22 



Cytoplasm — Nucleus — Centrosome — Plastids — Chondriosomes — Vacuoles 

 — Golgi Material — Ergastic Matter. 



CHAPTER IV 

 Protoplasm 44 



Physical Characters — Protoplasm as a Colloidal System — Chemical Nature 

 of Protoplasm — The Staining of Protoplasm — Conclusions. 



CHAPTER V 



Division of the Protoplast ."JG 



Somatic Cell Division in Plants: Mitosis and Cytokinesis — Somatic Cell 

 Division in Animals: ^Mitosis and Cytokinesis — Further Aspects of Cell 

 Division: C-auses of Anaphasic Chromosome Movement — Time Occupied hj- 

 Cell Division — The Shape of Cells in Tissues. 



CHAPTER VI 



The Cell Walls of Plants 75 



Development of the Wall — Minute Structvire of the Cell Wail — Plasmodesms 

 — Formation of Cellulose by the Protoplast. 



CHAPTER VII 



The Chromosomes 84 



Somatic Chromosomes — Meiotic Chromosomes — Salivary-gland ( 'liromo- 

 somes — Chromo.some Complements — Conclusions. 



CHAPTER VI II 



IMeiosis 102 



Distribution of the Chromosomes in the Meiotic Divisions — Detailed Ac- 

 count of the Phases of Moiosis — Problems of Mciosis. 



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