that will run out through the cannula and the immediate introduction of as much as one hundred cubic centimeters of the above mentioned iodin solution.  This solution is allowed to remain in the synovial cavity a few minutes and by compressing the tissues surrounding the tendon sheath, the evacuation of as much of the contents of the synovial cavity as is practicable, is effected.  Subsequently the subject is allowed absolute rest and more or less inflammatory reaction follows.  In some cases there occur marked lameness and some febrile disturbance, but where a good technic is carried out, no bad results follow.  At the end of four weeks’ time, horses so treated may be returned to service, but the full beneficial effect of such treatment is not experienced until several months’ time have elapsed.

Where good facilities for executing a careful technic in every detail are at hand, incision of the tarsal sheath, evacuation of its contents and uniting its walls again by means of sutures and providing for drainage with a suitable drainage tube, may be practiced.  This manner of treatment has been satisfactory in the hands of a number of surgeons.

Capped Hock.

Enlargements which occur upon the summit of the os calcis, whether hypertrophy of the skin and subcuticular fascia, the result of injury or repeated vesication, distension of the subcutaneous bursa or injury to the superficial flexor tendon (perforatus) or its sheath, are generally known as capped hock.  However, the term should be restricted to use in reference to distensions of synovial structures of that region.

Etiology and Occurrence.—­Usually there occurs a hygromatous involvement of the subcutaneous bursa due to contusion.  As in bog spavin, following certain infectious diseases (influenza, purpura hemorrhagica, etc.) there remains a distended condition of the subcutaneous bursa, after swelling of the member has subsided.  In feeding pens where numbers of young mules are kept in crowded quarters many cases may be observed.  In some instances where violent contusions result from kicking cross-bars of wagon shafts (by nymphomaniacs or in habitual kickers where there is opportunity for doing such injury) the superficial flexor tendon and its synovial apparatus are injured and a more serious condition may result.

Symptomatology.—­In acute and extensive inflammation of the parts, lameness is present, but in the average case no inconvenience to the subject results.  The prominent site of the affection is cause for an unsightly blemish.  This is undesirable, particularly in light-harness or saddle horses.  These affections are characterized by a fluctuating mass which has a thin wall and in all cases of long standing the condition is painless.

By careful palpation one may readily distinguish between a hygromatous condition of the superficial bursa and involvement of the underlying structures.  Affection of the expanded portion of the flexor tendon and contiguous structures makes for an organized mass of tissue which is somewhat dense and in some instances painful to the subject when manipulated.  This is particularly noticeable in cases where the parts are regularly and repeatedly injured as in habitual kickers.