PURPORT

In the reservoir of water first created by the perspiration of Garbhodakasayi Visnu, the Lord lies on the Sesa plenary expansion of Visnu, who is described in the Srimad-Bhagavatam and in the four as follows:

sahasra-sirsa purusah sahasraksah sahasra-pat
sa bhumim visvato vrtvatyatisthad dasaṅgulam

"The Visnu form called Ananta-sayana has thousands of hands and legs and thousands of eyes, and He is the active generator of all the incarnations within the material world."