The longitudinal muscle and the intern al anal sphincter in front of the upper part of anal canal were found to be blen ded with the perineal body.

• 耻骨直肠肌与前列腺提肌（或耻骨阴道肌）共同起于耻骨支后面和肛提肌腱弓前部，位于耻骨尾骨肌外下方同一层次上，两者间无明显分界。