REPRODUCTION 



161 



?, aft 



Fig. 63. Chromosomal changes in Holomastigotoides tusitala, X1050 

 (Cleveland), a, telophase shortly after cytoplasmic division, new fifth 

 band and new centriole are growing out and chromosomes are twisted; 

 b, c, the same chromosome showing major and minor coils respectively; 

 d, later telophase, showing minor coils; e, matrix completely disinte- 

 grated, showing minor coils; f, a prophase nucleus, showing division of 

 chromosomes into two chromatids; g, later prophase, in which majors 

 are developing with minors; h, later prophase; i, metaphase in which 

 distal halves of the chromatids have not yet separated, showing minor 

 coils; j, anaphase, showing major and minor coils of chromonemata. 



