THE NUCLEI OF UROLEPTUS MOBILIS 



321 



The third division figures are easily distinguished from those 

 of the first and second divisions by the greatly elongated con- 

 necting body between the daughter nuclei. In some cases these 

 connecting fibers attain a length of 30 n, and different stages of 

 division are frequently found in the same individual or in the 

 pair. The nuclear membrane plays the chief role in this con- 



Fig. 60 Late telophase of third division and formation of pronuclei (on right). 

 X 800. 



Fig. 61 Unusual phase in which eight daughter nuclei of the third division and 

 two undivided nuclei are present without pronuclei formation. X 800. 



necting fiber, the chromatin apparently forming no part of it 

 (figs. 62 and 63) . As the nuclei separate the walls come together 

 until they appear like a single connecting line (fig. 60). The 

 chromatin now separates into granules which become distributed 

 throughout the nuclear vesicle; the membrane closes and the 

 pronucleus is formed. 



