THE FORMATION OF GIANT POLAR BODIES IN CENTRIFUGED EGGS OF ILYANASSA

Abstract

These were produced by centrifuging the 2nd maturation spindle away from the animal pole. In some cases they underwent further development, evidently because the giant polar body received the sperm nucleus. At the close of the 2nd maturation division in centrifuged eggs, clusters of cyto-plasmic lobes distinct from the normal polar lobe appeared around the region where the achromatic figure lay. In strongly centrifuged eggs 5 zones of substances were separated; these included 2 clear zones separated by a band of fine granules.