148 



INTRODUCTION TO CYTOLOGY 



be drawn into a number of peculiar shapes. In the case of long chromo- 

 somes the portions to which the fibers are attached may have reached 

 the poles of the spindle while the other portions are not yet separated 

 at the equatorial plane. As soon as the daughter chromosomes become 

 entirely free from one another they quickly draw apart and contract 

 into two dense masses, which are often actually farther apart than were 



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Fig. 50. — Somatic mitosis in Tradescantia virginiana: metaphase (A), anaphase (B-D), 

 and telophase (E-G). At F are shown cross sections of chromosomes in the stage shown 

 at E. X 1900. {After Sharp, 1920.) 



the poles of the spindle at metaphase. In these masses the individual 

 chromosomes can be distinguished only with great difficulty or not at all. 

 With this stage, which has been referred to by Gregoire and Wygaerts 

 (1903) as the tassement polaire, the anaphase ends and the telophase 



begins. 



Telophase (Fig. 50, E — Fig. 51, 7). — After remaining tightly pressed 

 together for a short time the chromosomes of each daughter group begin 

 to separate, their individual boundaries again becoming visible. As they 

 do so they cohere at various points where their substance becomes 

 drawn out to form anastomoses. It seems clear that the main connec- 



