Castle. — Cioua intestiualis. 



PLATE IV. 



Eight successive views of a living egg, seen from the left side ; magnification, 315 

 diameters. Arrows indicate the direction of spindles. 



Fig. 19. Matured but unsegmented egg. 



Fig. 20. 2-cell stage. 



Fig. 21, 4-cell stage approaching. 



Fig. 22. 4-cell stage, " resting " condition. 



Fig. 23. 8-cell stage, just formed. 



Fig. 24. 8-cell stage, nine minutes later. 



Fig. 25. 16-cell stage, just formed. 



Fig. 26. 16-cell stage, some minutes later. 



