SOMATIC MITOSIS AXD CHROMOSOME INDIVIDUALITY 161 



f»f 





B 



a 



Fig. 56. — The chromosome complement of Vicia faba. 



A, B, two successive sections of a mitotic figure in the root tip, showing together the 

 12 split chromosomes, 2 of them about twice as long as the other 10. C, cross section of 

 the group of chromosomes at anaphase: each of the long chromosomes, beiim drawn pole- 

 wards by the middle, shows both ends, making the number apparently 14. I). K. two 

 successive sections of a heterotypic figure in the mierosporocyte, showing the 6 bivalents; 

 the large one is at the left. F, polar view of heterotypic mitosis at metaphase, showing the 

 6 bivalents. X 1400. (Original.) 



B 



Fig. 56 bis. 



A, anaphase of somatic mitosis in Crepis virene, showing 2 long, 2 medium Bised, and 2 

 short chromosomes passing to each pole. (After Rosenberg, L920.) B, the chromosome 



complement in a somatic cell of Najas major, showing the 7 homologous pairs. {After 



Tschcrnoyarow, 1914.) 



11 



