PART II. CYTOKINESIS. 



CONTENTS. 



t. Stkuctuee of Cytoplasm 



II. Movements of Cell Contents 



A. During Maturation 



B. During Fertilization 



C. During Cleavage 



1. First Cleavage 



2. Second Cleavage 



3. Third Cleavage 



4. Fourth Cleavage 



5. Fifth and Sixth Cleavages 



6. Subdivisions of First Quartette 



7. Subdivisions of Second Quartette 



8. Subdivision of Third Quartette 



III. Analysis of Movements during Cell Division 



1. Movements during Metakinesis . 



a. Movements in Spindle and Aster . 



b. Movements in the Cell Body 

 Comparisons .... 



2. Movements during Telekinesis . 



Comparisons .... 



3. Orientation of Centrosomes and Spindles 



a. Relative to Nucleus 



b. Relative to Cell Body 



IV. Some Factors of Diffeeentiation. 



1. Polarity .... 



a. Unsegmented Egg 



b. Blastoraeres 



c. Nucleus, Centrosome and Sphere 



2. Differential Cell Division . 



a. Rhythm of Division . 



b. Direction of Division . 



c. Size of Daughter Cells 



d. Quality of Daughter Cells 



References ..... 

 Explanation of Figures 



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