Srimad Bhagavatam Canto 06, Chapter 18, Text 62

SB 6.18.62

cakarta saptadha garbham
 vajrena kanaka-prabham
rudantam saptadhaikaikam
 ma rodir iti tan punah
 
Translation by His Divine Grace A. C. Bhaktivedanta Swami Srila Prabhupada: 
 
After entering Diti’s womb, Indra, with the help of his thunderbolt, cut into seven pieces her embryo, which appeared like glowing gold. In seven places, seven different living beings began crying. Indra told them, “Do not cry,” and then he cut each of them into seven pieces again.
 
Purport by His Divine Grace A. C. Bhaktivedanta Swami Srila Prabhupada: 
 
Srila Visvanatha Cakravarti Thakura remarks that Indra, by his yogic power, first expanded the body of the one Marut into seven, and then when he cut each of the seven parts of the original body into pieces, there were forty-nine. When each body was cut into seven, other living entities entered the new bodies, and thus they were like plants, which become separate entities when cut into various parts and planted on a hill. The first body was one, and when it was cut into many pieces, many other living entities entered the new bodies.
Srimad Bhagavatam Canto 06, Chapter 18, Text 61
Srimad Bhagavatam Canto 06, Chapter 18, Text 63