POLARITY AND BILATERALITY OF THE ANNELID EGG. 



75 



lated at the central end of the egg (upper end in the figure). 

 Innumerable cases of this kind are found in the preparations. 



Again, as already noted, the ectoplasmic granules tend to keep 

 within the ectoplasmic zone with low powers of the centrifuge. 



5.' -.-.- r.v-v '-- .-,.;>..-::>;-; & >;. .-;.: ".v:-i^V.S^jp- 1 . 



c 



FIG. 9. Section of an egg of Chtztopterus centrifuged 7,800 revolutions in one 

 minute at a radius of 6 cm. The egg was killed in Flamming' s fluid, and the fat 

 granules of the gray cap are stained black. The spindle blocks fat globules passing 

 in a central direction (/). /-/, primary axis; 2-2, secondary axis; ec., ectoplas- 

 mic spherules ; en., endoplasmic spherules in the distal hemisphere; /., fat globules 

 blocked by the spindle, g.c., gray cap ; h.b., hyaline band. 



But with higher powers they pass to the distal pole of the egg. 

 Nevertheless the ectoplasmic zone may be recognized without 



