Bacillus endospores can be positively identified using the MAA “Endospore test”. This consists of treating the sample with 3:1 MeOH:acetic acid (glacial) for 5 minutes followed by staining with any fluorescent probe. Alternatively, you may use Insti-Fluor Combo2 or Insti-Spore slides to achieve the same result. That is: the appearance of hollow fluorescent ovals, 1µm across. These have been called “Ghost Footballs”.
