In the hypocotyls of Rhizophora mucronata Lamk. and R. apiculata Bl. during viviparous germination the concentrations of chlorophyll (Chl) and total sugars, and net photosynthetic rate (P^) were increased quadratically, while linear relationship existed between starch content and the developmental phase. R. apicuiata hypocotyls had a higher value of as well as higher Chl, sugar and starch contents than hypocotyls of R. mucronata.