Fig. 
Fig. 
Fig. 
Fig. 
Fig. 
Fig. 
Fig. 
CASTLE, — Ciona intestinalis, 
PLATE IV. 
Eight successive views of a living egg, seen from the left side; magnification, 315 
diameters. 
Fig. 19. 
20. 
Arrows indicate the direction of spindles. 
Matured but unsegmented egg. 
2-cell stage. 
4-cell stage approaching. 
4-cell stage, “resting ” condition. 
8-cell stage, just formed. 
8-cell stage, nine minutes later. 
16-cell stage, just formed. 
16-cell stage, some minutes later. 
