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882 do so, and with each other, opening on the surface of the skin at the mammillated fistulæ already referred to. In the very rare red variety the colour of the accretions is red or pink. Under the microscope the mycotic elements can be readily recognized in the concretions. In microscopic sections of the tissues evidences of extensive degenerative changes, the result of a chronic inflammatory process, can be made out. An important feature as bearing on the pathology of the disease, and one which was long ago described by Lewis and Cunningham, has been insisted on more recently by Cunningham, namely, a sort of arteritis obliterans or extensive proliferation of the endothelium of the arteries and, according to Vincent, a thickening of the adventitia of the vessels as well as of the capillaries in the more affected areas.

Mode of entrance of the fungus.— Little is known on this point. It is conjectured that the fungi live as parasites on certain plants, and that they may penetrate the tissues of man through a wound in the skin. The peculiar endemicity and geographical distribution of the disease, and the facts of its occurring almost invariably on the feet or hands, and principally in bare-footed agriculturists, favour this view.

Treatment.— The only effective treatment, in the case of implication of a considerable part of the foot or hand, is amputation. This must be performed well above the seat of the disease; for it must be borne in mind that the long bones may be implicated as well as the small bones, and that unless- the entire disease be removed it will recur in the stump. Complete removal is not followed by relapse. If a toe, or a small portion of the foot or hand, is alone involved, this may be excised with success. Potassium iodide has been found to be beneficial in certain forms.

This term is used to indicate lesions, other than mycetoma, produced by the proliferation of certain yeast-like fungi in the tissues. Normally these fungi are either saprophytic or live as parasites on animals