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On one side of the hemisected pelvis, remove the viscera to examine the muscles that form the pelvic diaphragm, which separates the pelvis from the perineum. The pelvic diaphragm consists of two paired muscles, the levator ani muscle and the coccygeus muscle.

Links and References:
Grant's: 3.41
Netter (1ed.): 377, 337, 338 (2ed.): 373, 333, 334
Rohen/Yokochi: 323