Thats a picture of gas gangrene that resulted from untreated Septicemic plague. Bubonic plague is transmitted from fleas to animals such as rats and cats and prairie dogs. Two of the three kinds cause large red lumps and lymph nodes that are very swollen.
It is caused by a bacillus called Yersinia pestis and while the pneumonic type of plague is the most deadly, septicemic will cause death if left untreated. The bacteria cause what is called disseminated intravascular coagulation if left untreated, which will result in gas gangrene or tissue necrosis, hence the name black death.
Cool pic.
