145 Figure 22. Acrylamide gel electrophoresis in the presence of sodium dodecyl sulfate of extensively reduced bluegill white blood cell mem brane immunoglobulins fractionated by gel filtration. See Figure 21, right panel for the fractionation by gel filtration of pools 1 and 2. Panel 1; electrophoresis of gel filtration pool 1. Panel 2; electro phoresis of gel filtration pool 2. y = position of shark heavy chain L = position of shark light chain.