FIG. 6.

Life cycle of the endospore-forming C morphotype. Starting around sunrise, the cell divides at both cell poles. Intracellular offspring form by engulfment of these polar cells. Throughout the day offspring enlarge within the mother cell. Late in the afternoon, prior to sunset, the DNA within these offspring (forespores) takes on a rope-like configuration at the periphery of the forespore cytoplasm. The offspring mature into phase-bright endospores and remain dormant throughout the night. Prior to sunrise, the endospores begin to germinate and are released from the mother cell to repeat the cycle.