



1909] YAMANOUCHI— MITOSIS IN FUCUS I -j 7 



but is more active near the nuclear membrane. The fine ragged 

 material previously scattered throughout the central portion of the 

 nucleus moves toward the peripheral region and becomes trans- 

 formed into chromatin threads, leaving the central part of the cavity 

 comparatively free from chromatin (fig. 16) . The chromatin threads 

 become thicker and an eccentric distribution of them takes place 

 (fig- J 7)» until finally they are grouped in synapsis at one side of the 



cavity {fig. 18) . 



The chromatin threads, thus eccentrically grouped in synapsis, 

 have a certain regularity, i. e., they are not in a tangled mass or ball, 

 but are in groups of almost parallel loops, converging to a spot where 



membrane. While 



synapsis 



association with the threads in synapsis, the cytoplasm directly out- 

 side the membrane becomes transformed into dense kinoplasm. 

 not infrequently there are two synaptic groups (fig. 19) at two 

 opposite poles within the nucleus; and naturally in such cases two 



kinoplasmic accumulations appear in association with the two 

 synaptic groups. 



arms 



of each loop touching each other (figs. 20, 21). They now condense 



smaller 



tached from the spot where they lay during synapsis. Each of these 



(fig 



applied to each other, 



chromosome 



,, . so that the whole chromosome 



M spherical mass. Such is the condition of pre 

 ate prophase a single centrosome aDDears in 



Qiakin 



(fig 



devekT' appearance later - Radiations and achromatic spindles 

 att^V 11 connecti °n with the centrosomes. The spindles then 



akr 1. 1 me cn romosomes 



abkshed (fi gm 24) . 



It 18 i'tvit-^^. . . 



spirem 

 somes. 



in 



chromatin 



and 



threads in synapsis, which have arise 

 delicate ragged chromatin reticulum 



