Average Raman spectra and difference spectra of dormant and superdormant spores of Bacillus species. The average Raman spectra of 50 individual B. subtilis superdormant spores (curve a), dormant spores (curve b) and their difference (curve a-b) (A); B. cereus superdormant spores (curve a), dormant spores (curve b) and their difference (curve a-b), multiplied by a factor of 3 for display (B); and B. megaterium superdormant spores (curve a), dormant spores (curve b), and their difference (curve a-b), multiplied by a factor of 3 for display (C).