Amylases of bacteria, barley, sweet potatoes, and white potatoes were separated by electrophoresis in polyacrylamide gels containing soluble starch. After incubation in acetate buffer and staining in iodine solution, the zones of enzyme activity remained unstained. The zones of crystalline α-amylase (bacillus subtilis) and of crude α-amylase (bacteriae) were found to be identical. The main zone of the crystalline β-amylase (lpomoea batatas) was identical with the zone of crude β-amylase (barley) and with the amylase zone of the potato (solanum tuberosum) extracts. Using 5 mm slots, 1 ng of amylase is traceable. Crystalline β-amylase yielded, in addition to the main zone, a minor zone nearer to the anode. The α-amylases had three zones of different properties. Phosphorylases were demonstrated as starch synthesizing and as starch degrading enzymes by making use of the reaction: “glycogen +glucose-1-phosphat⇌starch +phosphate”. Glycogen was polymerized into the gel to demonstrate the synthesis of starch, and incubation was carried out with glucose-1-phosphate. The starch formed was stained with iodine. The extracts of freshly harvested tubers yielded four zones, whereas those of stored tubers yielded two zones, and leaves and sprouts each showed one zone. - To observe starch degradation by phosphorylases, starch was polymerized into the polyacrylamide, and the gels were incubated in phosphate buffer. After treatment with iodine, an unstained zone was observed which corresponded to the most intense phosphorlase zone (close to the anode) in the glycogen gel. This zone was more intense in the tuber extracts than in leaves and sprouts. Pig heart extract contained the phosphorylase in the b form. Three zones have been observed. - Extracts of rat muscle and heart yielded phosphorylases which corresponded in their migration rate and in their requirement for adenosine-5′-monophosphate to the b form of pig heart phosphorylase. The same was true for the migration rate of liver phosphorylase. Crystalline α-phosphorylase of rabbit muscle required the addition of cystein to the electrophoresis buffer during separation. Two zones of activity could be demonstrated.