The evacuating channel separately became manifest, and the director named Mitra entered into it with partial organs of evacuation. Thus the living entities are able to pass stool and urine.
Srimad Bhagavata Purana
श्रीमद्भागवतमहापुराणम्
मूल श्लोकः
गुदं पुंसो विनिर्भिन्नं मित्रो लोकेश आविशत् । पायुनांशेन येनासौ विसर्गं प्रतिपद्यते
gudaṃ puṃso vinirbhinnaṃ mitro lokeśa āviśat | pāyunāṃśena yenāsau visargaṃ pratipadyate
SB 3.6.20