THE REDUCTION OF THE CHROMOSOMES 



23' 



Animals 



von Winiwarter 

 Marechal 



1900 



1904, '05, '07 



A. and K. E. Schreiner 1906, '07, '08 



Rabbit, Man 



Tunicates, Selachians, Teleosts, Am pin- 

 ox us 



Tomopieris, OphryotrochOf Zodgonui, 

 Enteroxeno8 t Myxine, Salamandra^ 

 Spinax 



( 'yclojM 



Thy8anozoon 



ZoogoniiA 



Batracoseps 



Alytes 



Planaria 



Dytiscus 



Euschislus 



Hersilia, Enchenopa 



Phrynotettix, Chorthipptu 



Cambarus, Cancer 



Canis 



Mus 



Insects 



RUT 



HlTCROTIfll niTOSIJ 



if-UKI) CONTRACTION 



Honorific riiioiti 



;u» sriun 



».»«l«tJli 



Fig. 89. — The method of chromosome reduction according B. 



Explanation in text. 



Scheme B. — The second of the two conspicuous interpretations was 

 advanced by Fanner and Moore (1903, L905), and i ntially as 



follows (Figs. 89-92): In the early heterotypic prophase the reticulum 

 becomes more thready in structure and contracts into a tight knol 



(synizesis). When this knot loosens up tin' chromatic material has 



