Scanning electron microscopy of baboon spermatozoa.

Ejaculated baboon sperm was observed by scanning electron microscopy. The plasma membrane was generally smooth except on the acrosome where it was probably slightly wrinkled. The head was short, oval, paddle-shaped and tapering at its anterior end. The anterior segment of the acrosome was surrounded by a marginal thickening; the postacrosomal region was limited anteriorly by the equatorial segment and caudally by the posterior ring. Subsurface structures were visible in the tail, such as the relatively long and regular helix of mitochondria in the middle piece and the columns and ribs of the sheath in the principal piece. The morphology and dimensions of the baboon sperm was compared with that of other Primates and found very close to that of other Cercopithecidae.