Two novel homologous series of hydrogen bonded liquid crystals (HBLC) comprising of 14 mesogens are formed between Methyl Malonic acid (MM) and p-n-alkyloxy/alkyl benzoic acids (nBAO/nBA). FTIR study confirms the formation of hydrogen bond. Phases exhibited by thesemesogens are characterized by optical textural studies and Differential Scanning Calorimetry (DSC) studies. Phase diagram is constructed fromthese studies. Other thermal parameters such as order of the transition, thermal stability factor and specific heat are also elucidated. Optical tilt angle measurement and optical filtering action are also carried out. The influence of oxygen atom is also discussed.