PLATE 2 



EXPLANATION OF FIGURES 



Climax 



14 Main culture I, Line c, 426th generation, April 9, 1908. Old marronu- 

 cleus merely in the form of a membrane from which the numerous chromatin 

 bodies have been ejected and are free in the cytoplasm. Eight so-called reduc- 

 tion micronuclei two of which are lying isolated; the others in groups of three. 



15 Main culture, Line b, 1498 to 1499th generation, December 12, 1909. A 

 division stage at the climax of the process. Numerous chromatin bodies in each 

 sister cell. One shows a membranous remnant of the old macronucleus. Each 

 has only one micronucleus. 



16 Mass culture started from main Culture I, October 12, 1913 (see page 435). 

 One cell is in same stage as both cells in figure 15. The other cell shows the for- 

 mation of the macronuclear anlagen, several chromatin bodies and two micro- 

 nuclei. 



17, 18 and 19 Culture B, Berlin race, October 6, 1913 (see page 473). Three 

 animals illustrating the details of the formation of the macronuclear anlagen. 

 Figure 17 shows two micronuclei, one macronuclear anlage completed and the 

 other macronuclear anlage just beginning to be evolved from a micronucleus. 

 Figure 18 shows two micronuclei and two completely formed macronuclear an- 

 lagen. Figure 19 shows the same except that the micronuclei have divided for 

 the next cell division. Tn these three figures the chromatin bodies have been 

 omitted. The cells have been counterstained with eosin. 



20 Subculture IE, Line Via, 4084th generation, December 4, 1913. Animal 

 shows two macronuclear anlagen which have lost their initial form. Chromatin 

 bodies beinning to disintegrate. Two micronuclei. 



21 Subculture IE, Line VI, 4107th generation, December 16, 1913. The same 

 stage as shown in figure 20, except that one of the micronuclei has completed divi- 

 sion and the other is in process of division: 



22 Subculture IE, Line III, 4063d generation, November 23, 1913. Essen- 

 tially the same stage as former but showing both micronuclei in division. 



23 Main culture I, Line c, 1755th generation, May 1, 1910. Animal figured 

 to show that the complete reorganization of the cell occurred in the same manner 

 at a relatively early period in the history of the main race. 



24 Culture B, Berlin race, ^NFarch 15, 1913. Animal figured to show that the 

 complete reorganization occurred in an animal from a different race. Only one 

 micronucleus is evident, the other being obscured by the chromatin bodies. 



508 



