Notes on the life history of the planktonic alga, Dysmorphococcus globosus (Volvocales)

Several strains of Dysmorphococcus globosus, a planktonic greenflagellate, were examined during this study. Dysmorphococcusglobosus has a generation rime of 48 h, at which time four bi-flagellateddaughter cells were released. In some instances, four to eight,rarely 16, noo-flagellated aplanospores will be formed per cell,germinating when placed in fresh medium with the subsequentrelease of from one to four motile individuals. Sexual reproductionwas recorded in detail for the first time although it had beenpreviously reported that pairs of individual cells had beenobserved attached at their anterior poles. Sexual reproductionwas isogamous to anisogamous with the clones being homothallic.During zygote germination, the zygote undergoes two rapid divisionsto form four products of meiosis which were released followingrupture of the lorica.