FIG. 8. Silver preparations of cells belonging to new type of clone whose origin 

 was diagrammed in Fig. 7. A and B are photographs at two optical levels of same 

 animal. Note two complete oral meridians about 90° apart (instead of tbe 180° 

 separation typical of normal doublets). C is another type of cell frequently produced 

 in this clone; it differs from the others only in having three instead of two cyto- 

 pyges. The animals of this clone have only one dorsal surface and in it only one 

 contractile vacuole pore meridian or narrow segment. (ir, anterior right kinety field; 

 al, anterior left kinety field; m. mouth; pr, posterior right kinety field; pi, posterior 

 left kinety field; py, cytopyge; s, preoral suture. 



183 



