We have studied the 3D structure of lamellar domains in aqueous solutions of nonionic surfactant C16E6 and C16E7 below the Krafft temperature by means of confocal microscopy. A new morphology of lamellar domains has been found in the C16E6 system, which is the network of lamellar domains. In the C16E7 system, we have confirmed that the spherical vesicles have a hollow including excess water. Furthermore, we have investigated the initial formation process of lamellar domains in those two systems. It has been found that initial lamellar domains of both systems are tiny and plate-like and that the domains are gradually curved in the C16E7 system, while in the C16E6 system, they spread to fuse together and form networks.