62 



masses. These "become irregular in form, and at the same 

 time fuse with one another, so that their number is re- 

 duced by more than half (fig. 120) , At this stage they are 

 in the form of thick, curved rods, in v/hich light and dark- 

 ly sta.ining a,reas rae-y oe discovered. Often four dark areas 

 may be detected i i each rod, v/liich sviggests that this 3,tage 

 corresponds to the formation of tetrads in the oocytes 3-nd 

 spermatocytes of many aniiaals, Coincidently v/ith these 

 changes, small granules- are to be seen in the nucleus near 

 its periphery, \/hich seem to pass out into the cytoplasm 

 (fig. 121), to form the granules alr*eady mentioned as oc- 

 cuj-'ing in the vacu^tir ai^ea. 



The stage just desci-'ibed is considered to be the pe- 

 riod of s^Tiapsis, It is of long dura,tion, it shows a con- 

 dition which does not occur elsev/here in the life history, 

 and it immediately precedes the mitoses in v/hich nvunerical 

 reduction of the chromosomes takes place. It differs from 

 the usual type of sjTiapsis in that no spirem or synaptic 

 tlirecid is formed; but tjiis is not to be wondered at inas- 

 much as nowhere in the life history of Griffithsla Bornet - 

 iana is a spirem produced. Perhaps tlie worm-like nuclear 

 masses are to be considered as replacing the usual spirem 

 stage. 



