It is not an easy matter to diagnose between the advanced stages of non-malignant rectal ulcer and cancer. Both may be accompanied by tender, condylomatous growths or flaps of skin outside the anus, bathed with an ichorous fluid. The characteristic, unremitting pain of cancer may be absent in its formative stage, and in this respect insidious in its approach, the same as the non-malignant ulcer. Allingham speaks of a very rare species of rectal ulcer, which he terms rodent or lupoid, that is superficial, does not implicate the surrounding parts, devoid of hard edges or surface, very painful and only cured by complete extirpation. I have intentionally omitted the early symptoms and course of rectal ulcer for the purpose of giving audience to Dr. A. C. Hall, who, in a communication to a medical journal, writes the following lucid description: “Rectal ulcer is a more common disease than is generally supposed. Unfortunately the symptoms are generally obscure, and the patient suffers but very little, if any pain, and consequently consults his physician for some of the reflex symptoms, rather than for the initial disease itself; and very often these reflex symptoms are vainly treated till the patient and physician are both thoroughly disgusted and disheartened. There is one maxim which every physician should always bear in mind, and that is, _always suspect rectal ulcer in every case of protracted or chronic diarrhœa_. I have reports from eighty-six pension surgeons, in which they estimate that they have examined two thousand cases, where chronic diarrhœa was the alleged cause of disability in applicants for pensions. Of these two thousand cases of chronic diarrhœa, eighty-seven per cent. had rectal ulcers, and fully ninety per cent. of those who claimed chronic diarrhœa as their disability and who had no ulceration were rejected, because their proofs of the disease, aside from the ulceration were too meagre. Thus the strongest and most prominent symptom of rectal ulcer is _chronic diarrhœa_.