In chronic and neglected suppurating corn, in untreated quittor, and in long-standing complicated sand-crack, for instance, we have conditions in which pus and other septic matters find ready entrance into the subcoronary tissues.  Should either of these be neglected, or should the pus formation from the onset take on a slow but gradually spreading form (in other words, should either of these cases run a chronic rather than an acute course) then, with the persistence of the inflammatory phenomena so caused, is bound to result a steady and increasing growth of inflammatory fibrous connective tissue.  This, as it grows, becomes in its turn penetrated by the ever-invading pus, and, under the stimulus thus caused, itself throws out new tissue.  And so, constantly excited, the tumour-like mass tends to steady increase in size, until enlargements are formed which one may sometimes truly term enormous.

Symptoms.—­The appearance of the growth is, of course, immediately evident.  Usually these swellings are slow in forming, so that the size of the enlargement depends entirely upon its age.  We may thus meet with growths of this description, varying in weight from 4 or 5 pounds to the almost incredible size of 33-1/2 pounds.  In the majority of cases a discharging sore is to be found upon it—­in some cases several.  Explored, these sores reveal their true nature.  Their lip-like openings, and the ready manner in which they may be searched by the probe, show them to be sinuses.

In a few cases, however, the outer surface of these tumours is intact.  When this is the case, it is possible that the growth is a true fibroma—­that is to say, a non-inflammatory new growth of fibrous connective tissue.  On the other hand, it may have resulted from one or other of the causes we have enumerated, and its exact diagnosis have been impossible until operative measures had been proceeded with.  In this case, small and encysted foci of inspissated pus scattered more or less throughout the growth indicate its true nature.

Pain as a rule is absent, and, unless the growth, on account of its size, interferes with progress, the animal walks perfectly sound.  Here the patient may, without offending the dictates of humanity, be put to slow work.

Treatment.—­In very many cases, possibly on account of the decreased circulation and vitality of the parts, these growths occur in aged animals.  Here treatment is not economic, and may for that reason be put out of the question.  Further, the growths are more common in heavy cart animals of a lymphatic type than in those of a lighter breed.  Couple this with the fact that the tumour is often unattended with pain, and we see that the animal is still able to perform his accustomed labour.  Here, again, treatment is contra-indicated.

For still another reason surgical treatment, which is the only treatment likely to be of benefit, must not be undertaken rashly.  A large and open wound is bound to be left behind.  So large is it in many cases that the complete covering of the exposed surface with epidermal growths from the circumference cannot possibly be looked for.  There is then left a large and horny-looking scar, which is an even worse eyesore than was the original enlargement.