Each organism has its own strategy to survive harsh times. Many centric diatoms manage by forming resting spores. A resting spore is not able to reproduce, it builds a thick silica cell wall and, because it is heavier than vegetative cells, it sinks to the sea bottom, awaiting better times. This picture shows that three of the six cells of the centric diatom Bacteriastrum hyalinum (Bacillariophyceae) are creating resting spores. When counting from left to right, in the 3rd, 5th and 6th cell, one of the two thick bent outer cell walls of the spore can already be noticed. As soon as its formation is finished, the spore will detach from the maternal cell and sink to the bottom.