37 



(fig. 57), Each protuberance is at first hemispherical and 

 about 20-25 »«^ in dieoneter. There ie in each a single nu- 

 cleus, surrounded "by dense, clear cytoplasm, which is in 

 free coirununication v/itli tliat of the mother cell (fig. 5C) . 

 Their formation is not connected \/ith nuclear division, "but 

 takes place v;hile the nuclei are in the resting condition. 

 The withdrawal of so manj- nuclei from the upper portion of 

 the parent cell leaves this region almost free of nuclei 

 (fig, 57). As grcv/th proceeds, however, nuclei v/ander up 

 from the "basal region, and become aga-in evenly distributed 

 in the cytoplasm. 



Each primari' protubers.nce is soon cut off from the 

 motlier cell b;'' b. delicate partition, which is laid dov-m by 

 the protoplasm in the same way as in the first method of 

 cell division described on pages 25-2fe{ fig. 59). When its 

 formation is complete, the prima,ry protuberance divides 

 several times vertically (figs. 61 ^60), A lateral cyto- 

 plasmic process is formed, then the nucleus divides by mi- 

 tosis (figs. 61,60). One daughter nucleus remains in the 

 body of the primary protuberance, the otlier passes into 

 the cytoplasmic process. The two protoplasts nov/ become 

 separated by a constriction of the Iiautschiclit , whose in. 

 grov/th appears to be aided by the formation of a vacuole 



