it 





Fig. 2. Adenosinetriphosphatase in frozen-dried rat sperm, (a) Trans- 

 verse and (b) longitudinal sections of epididymal sperm incubated in 

 ATP, CaCL, cysteine, veronal buffer pH 9. The peripheral fibers are 

 densely "stained" compared to sheath, axial core, and matrix. Controls: 

 (c) ATP-free medium; (d) CaCl 2 -free medium (X 9,000). 



175 



