104 



LECTURE VII. 



' The division of the nuclear disc (which consists of nuclein rodlets) is ac- 

 complished in the equator, and both halves separate from one another. Elements 

 which lie in the equatorial plane, or run through it, undergo division. With granules, 

 rods, and rodlets, this takes place simply by constriction. If the nuclear disc 

 consists of accumulated granules or rodlets, one part goes over on the one side, the 

 other part on the other. The process is more complicated in nuclear discs which 

 present filaments placed equatorially. These form mostly two or more legged 

 figures, with the ends of the legs turned outwards. The figures become doubled 



Fig. 105.— Cbanpes of the cell 

 yyagrans ; 4 — 8 from Allittin odon 

 magnified). 



The dark portions ; 



-3 from the endospern 

 the Nuclein (after Fie 



ling : ! 



into two similar ones, or now pass over to the corresponding daughter-nuclei in 

 such a manner that their fused ends are directed towards the pole, their free ends 

 towards the equator.' 



' Diuing the development of the daughter-nuclei,' proceeds Strasburger, ' they 

 are usually nourished at the same time from the surrounding protoplasm, that 

 they may grow up to the size of the mother-nucleus. This may be followed very 

 well in Spirogyra, on account of the free suspension of the nucleus in the cell. All 

 the protoplasm collected at the polar side of the daughter-nucleus, and here forming 



