In morphogenesis of the Late Cretaceous skeletal sponges – hexactinellids – certain tendencies may be traced that allow to distinguish forms of diverse levels of modular organization (≪polyoscula≫ sponges) among the unitary representatives of the group. Skeletons of the sponges from the primary level of modular forms, autonomies, represent an example of the initial module polymerization, with the principal polymerization mechanism involving diverse variants of gemmation and/or fission