Search

Growth rate and morphological characteristics of Dictyosphaerium pulchcllumwere observed from populations maintained at 20 and 25 C under light intensities varying from 100 to 1200 ft‐c. Growth rates, expressed as the number of times the population doubled in chlorophyll content per day, were 0.57 (100 ft‐c) and 1.71 (1200 ft‐c) at 20 C and 0.80 (100 ft‐c) and 2.S7 (1200 ft‐c) at 25 C. Cell size varied between 3.0 and 7.0 μ among all treatments at 20 C and mean cell size increased with an increase in light intensity. Agitation of asexually reproducing populations resulted in up to 95% of a population occurring in a unicellular form. The percentage of uni‐cells was highest in vigorously agitated test tube cultures.