The economy of dry matter was analysed in relation to the growth and matter production of Pteridophyllum racemosum, an evergreen perennial herb of Papaveraceae grown in the subalpine coniferous forest (2 ,250 m in altitude) of northern Yatsugatake Mountains, central Japan. Annual respiratory loss of dry matter estimated from the seasonal change in respiratory activity of each orgen was 1.35 g/m2 and corresponded to about 77% of the gross production, which was accounted to be 176 g/m2 . year as

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... he sum total of the net production and the respiration. Daily gross production was highest in early growing season. Measurements of the seasonal changes in the photosynthetic activity and the biomass of leaves of each age led to the conclusion that one-yearold leaves played an important role in matter production of the population in this season. Two main phases were recognized in the annual matter economy of the plant . In the first phase, till the end of June, above ground new organs grew rapidly