In FeTiO₃, CoTiO₃ and NiTiO₃ the dominant magnetic exchange interactions are held to be of super-superexchange type, using two oxygens or one oxygen and one diamagnetic Ti⁴⁺ ion between the pairs of paramagnetic cations. In order to explain the antiferromagnetic ordering of manganese spins in the same layer in MnTiO₃ it is suggested that the metal cations are Mn⁴⁺ and Ti²⁺, the interactions being of the same superexchange types as those previously suggested for Cr₂O₃.