SB 4.1.36
pulastyo ’janayat patnyam
agastyam ca havirbhuvi
so ’nya-janmani dahragnir
visravas ca maha-tapah
Translation by His Divine Grace A. C. Bhaktivedanta Swami Srila Prabhupada:
Pulastya begot in his wife, Havirbhu, one son of the name Agastya, who in his next birth became Dahragni. Besides him, Pulastya begot another very great and saintly son, whose name was Visrava.