Striations in the Peripheral Fibers of Rat and Mouse Spermatozoa

936 it is known that each fiber has a narrow cortical zone which appears more or less dense (depending on the methods of preparation) than its center . or medulla (Telkka, Fawcett, and Christensen, 1961). Phosphotungstic acid appears to stain the cortex selectively, leaving the medulla unstained, and the demarcation between cortex and medulla is shown to be clearest in the abaxial segment of the fiber (Gordon and Bensch, 1968) . The