of a large sloughing sore. Though occasionally fatal, these sores almost always, under favourable conditions, granulate and cicatrize, or become chronic ulcers.
Geographical distribution.—Sloughing phagedæna is common in most tropical countries, particularly in those with a hot, damp climate. These sores are often named after those districts in which they are specially prevalent; thus we hear of Mozambique ulcer, Yemen ulcer, etc. They are found principally in jungle lands, less frequently in towns and well-settled districts. Whether tropical sloughing phagedæna and hospital gangrene, at one time so prevalent in the hospitals of Europe, are the same disease, it is difficult to say. They agree in some respects; but in the marked tendency of the tropical sore to self-limitation, and, possibly, as Scheube points out, in its relatively feebly infective power, there is some indication of a specific difference.
Occasionally this disease assumes epidemic proportions. Thus, Lloyd Patterson (Ind. Med. Gaz., Nov., 1908) described one such epidemic which "swept like a plague up the whole of Assam," seriously interfering with the efficiency of the labour force on the tea plantations.
A variety of bacteria and spirochætes have been described as possible germ causes of this disease. Vincent remarked the frequent concurrence of spirochætes and fusiform bacilli in the sores, an observation confirmed by several others, including Todd and Wolbach on the Gambia. Prowazek attributes these ulcers to Spirochœta, schaudinni. Lloyd Patterson has called attention (loc. cit.) to a bacillus occurring in scrapings from the base of the ulcers, which he considers as the probable germ, and which had hitherto been overlooked in consequence of the difficulty in staining it, prolonged immersion in Leishman's stain being necessary.
Although sloughing phagedæna is evidently a germ disease, it is not readily communicated by ordinary inoculation either to man or to the lower animals. Apparently a concurrence of certain unknown conditions is essential. Lloyd Patterson,
