PLATE 6 
EXPLANATION OF FIGURES 
CUMINGIA (25-31) AND CEREBRATULUS (32-35) 
25 Centrifuged at polar spindle stage; spindle being pushed back by yolk 
bent fibres. 
26 Centrifuged 40 turns at dissolution of pronucleus. 
27 Centrifuged 40 turns at 2-cell stage. The egg had additional male pron- 
nuclei or else had a polyaster, but divided into two cells of unequal size. 
28 Centrifuged while going into 2-cells. 
29 Centrifuged while going into 2-cells. 
30 Centrifuged 70 turns at early pronuclei or before, continued on water 
centrifuge till 2-cell. 
31 Centrifuged 40 turns as two nuclei reformed. Shows nuclear sap extending 
shows to oil cap. 
32 Cerebratulus. Bent segmentation spindles in small piece of egg. 
33 Centrifuged segmentation spindle. 
34 Centrifuged segmentation spindle. 
35 Centrifuged at 2 pronuclei; killed 2-cell. 
