Clostridium botulinum. These bacteria produce the toxin responsible for botulism - sometimes found in under-sterilized canned foods. Some of these are shown lysing (dying) as toxin builds up over a five day period (9a), some are shown as spores (the bacteria with the bright holes in them, 9b). The spores are very refractile making them appear as they do. When heated, the spores germinate producing more bacteria which can then divide by binary fission.