Pseudogap phenomena, which are associated with the reduction in the density of states at EF, have been intensively investigated in HTSC, as well in heavy fermion systems through the optical conductivity (OC) and inelastic neutron scattering (INS) measurements. OC measures the charge gap in charge degrees of freedom, while INS measures the spin gap in spin degrees of freedom. The recent OC study of BaRuO3, which has three different crystallographic forms depending on the number of BaO3 layers, reveals a pseudogap formation at EF in the insulating rhombohedral (nine-layer) 9R-BaRuO9 as well as in the metallic hexagonal (four-layer) 4H-BaRuO3 with gap energies of 100 meV and 80 meV, respectively. We propose INS study on 9R-BaRuO9 and 4H-BaRuO9 to investigate whether there exists a spin gap in these compounds. If such a spin gap exists then we propose to investigate its T and Q dependence.