Ii 



CYTOLOGY 



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Fig. 15. — Diagrammatic comparison of 

 mitosis and meiosis. Maternal 

 chromosomes are shown in white, 

 paternal ones in black. 



{After Sharp.) 



First column — Somatic mitosis. 



Second column — Meiosis : heterotypic 

 and homotypic divisions. 



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The essential features of the process are the following : The first stage, 

 formerly called the heterotypic division, begins with the separation from 

 the reticulum of the diploid number of chromonemata. The two members 

 of each homologous pair then come together side by side, the process being 



