GERM CELLS IN NEMATODES, SAGITTA 175 
somes intact. A similar reduction in the amount of 
chromatin takes place in the fourth and fifth divi- 
sions and then ceases. The single cell in the 32-cell 
stage which contains the full amount of chromatin 
Fic. 51.— Ascaris. Stages in early cleavage showing the chromatin- 
diminution process in all cells except the stem cell (S). (From 
Boveri, 1892.) 
has a larger nucleus than the other thirty-one cells 
and gives rise to all of the germ cells, whereas the 
other cells are for the production of somatic cells 
only. The cell lineage of Ascaris is shown in the 
accompanying diagram (Fig. 52). 
