The cladistic relationship among 34 species of the genus Calandrinia H.B. et. K. (Portulacaceae), endemic to Australia were analysed for 22 binary attributes, by using "PHYSYS" computer program. The criteria used to assign evolutionary polarity of attribute state is discussed in detail. In all the Phenograms four main groups came out fairly clearly. The major difference in the trees produced by PHYSYS are the changes in the position of a few taxa, within the major group. The present paper provides data on variation and correlations in seed and pollen characters, and also synthesized detailed morphological relationships. The species having questionable position in some group are discussed in the light of their unique characters.