SB 9.21.35
tasya satyadhrtih putro
dhanur-veda-visaradah
saradvams tat-suto yasmad
urvasi-darsanat kila
sara-stambe ’patad reto
mithunam tad abhuc chubham
Translation by His Divine Grace A. C. Bhaktivedanta Swami Srila Prabhupada:
The son of Satananda was Satyadhrti, who was expert in archery, and the son of Satyadhrti was Saradvan. When Saradvan met Urvasi, he discharged semen, which fell on a clump of sara grass. From this semen were born two all-auspicious babies, one male and the other female.