We observed self-organized plates growing in some mesogenic mixtures as the first stage of nucleation of the mesomorphic phase and transformation of the plates into multiphase bifilar filaments (called nematoids). The liquid crystal plates and subsequent nematoids are freely suspended inside the isotropic melt. The creation of the plates and their transition to nematoids were observed in mixtures of nematic, smectic B and non-mesogenic chiral dopant. The maximum size of the plates depends on the concentration of the mixtures and varies from 0.1 to more than 1 mm. Study of the fringe deflection profiles in Pluta birefracting microinterferometry revealed that the nematoids have bifilar internal organization. Two modes of creation of the nematoids can be distinguished : (a) formation of initial toroidal droplets and then nematoids and (b) intermediate formation of nematoids by rolling of the plates. Four main types of temporal and thermal evolution of the nematoids can be specified : (a) immediate fast shrinkage to droplet, (b) segmentation, (c) splitting along the longitudinal axis, and (d) double-spiralling. In all cases, the final stage of evolution is a liquid crystalline droplet which can be a source of secondary nematoids growing at diminished temperature.