A preliminary account of the synthesis and liquid crystal properties of representative members of an homologous series of 5-alkanoyl-5 "-alkyl-2,2’:5’,2 "-tertbienyls and the analogous 5,5 "-di-alkyl-2,2’:5’,2 "-terthienyls is given. The disposition of the three thiophene rings renders the molecular geometry sufficiently anisotropic that suitably substituted compounds are mesomorphic, and the liquid crystal transition temperatures of corresponding members of the two series are compared. The related 5, 5’-disubstituted 2, 2’-bithienyl derivatives are not mesomorphic.