Stickelback Eggs

This educational film, presented in two parts, functions as a microscopic documentary. Shortly after the egg is placed in water, fertilization begins, followed by contractions. Inside the fertilized egg, the germinal disc divides into two blastomeres, with continued divisions occurring as contractions reappear at the cap covering the egg. French title cards provide guidance on what to observe. The film shows muscular movements and the development of circulation, including the beating of the heart. In the second part, the onset of blood circulation is depicted as red blood cells form on the surface of the yoke and gather toward the heart. Arteries develop, and blood begins to flow. As the egg hatches, blood continues to circulate into new areas.