Abstract
Histochemical demonstration of acid polysaccharides was carried out on hamster eggs just after ovulation through just before implantation, using alcian blue stain. Although no acid polysaccharides were found in the egg cytoplasm at any stage, a large amount was observed evenly spread throughout the zona pellucida of penetrated, pronuclear and cleaved eggs, and somewhat in smaller amount in that of blastocyts. In 8-celled eggs, acid polysaccharides appeared also in the perivitelline space adhering to the blastomere surface, while in naked blastocysts, such substances appeared adhering to the trophoblast surface. This paper dealt with the origin of these acid polysaccharides especially in the perivitelline space as well as their physiological significance.
