There occurs rarely on the skin a lesion resembling an ulcer that spreads slowly and obstinately with a gangrenous border. It often is connected with, and evidently arises from, a preceding suppurative lesion and usually occurs in a person afflicted with some debilitating disease, but in the case reported here it was not so associated. On the contrary, neither ulcerative colitis nor other suppurative disease was present. The patient, it is true, had been under a heavy strain for some months, attending an ailing sister and holding her position as bookkeeper, entailing both excess of work and loss of sleep. This gangrenous process, attributed, as in the present case, to a streptococcus, is now more than usually interesting because of the remarkable influence of sulfanilamide on streptococcic diseases. I report a failure of sulfanilamide after two trials in this case. The disease has a bewildering number of names, and I