This also belongs to the diseases frequently complicated by lesions, aside from those of laryngeal obstruction calling for surgical relief. Abscess occurs so frequently as to scarcely call for comment. Here, as in the cases of scarlatina, the location of the throat lesions and the absorbing powers of the lymphadenoid tissue so completely involved will readily account for all septic or pyogenic manifestations at a distance. Multiple abscesses have been found in the liver, the spleen, and lungs, in and around bones, betokening thereby a pyemic manifestation. Infectious nephritis is also common. Mann, of Denver, has communicated to me personally cases of embolus of the femoral artery with resulting gangrene as sequels of diphtheria, as well as instances of true diphtheria of the penis, established by bacteriological diagnosis. MUMPS. The infectious character of this disease is not questioned, although not definitely established. Orchitis, ovaritis, stomatitis, enlargement of the tonsils and spleen, and albuminuria are frequent accompaniments of the disease, while articular and peri-articular complications have been noted. Bursal abscesses and pyarthroses have also been reported. These surgical complications have been regarded as rheumatoid or rheumatic, their essential significance not being recognized until recently. VARIOLA. The writers of the earlier part of this century allude frequently to the rheumatoid complications of smallpox, among which pyarthrosis seemed the most common and most serious. The various arthropathies are the most interesting of the surgical complications of this disease. The joints become swollen, red, and painful, one joint after another being involved. INFECTIOUS ENDOCARDITIS. The individuality of this condition has been recognized only within the last thirty years. That it deserves the characterization of “malignant” often given to it is well known. It is an infectious disease with a special localization in the heart, the term _cardiac typhus_ being very expressive. Although so apparently spontaneous, it is usually a secondary lesion, sometimes a primary infection. The arthritic manifestations often assume a pyemic character, and even at the beginning of the affection, as Trousseau pointed out, there are frequently severe joint pains. DENTAL CARIES.