FORMATION AND GERMINATION OF RESTING SPORES OF Chaetoceros didymus EHRENBERG (BACILLARIOPHYTA)

Resting spores are important in ecology and taxonomy of diatoms as well known to every dia-tomist.If NO₃-N and NO₂-N in the cultures drop down to 4 μg I^-1, or at a relatively small amount of N, higher in number of individuals and sudden increasing of salinity, the resting spores will produce after 24 h.Paired spores are present in the newborn spore-mother cells.At 20℃ and 6000 lx in a fresh medium, spores will be germinated into vegetative cells within 48 h.