occurs without obvious cause, or any affection of the joint. When the disease is advancing, the patient may feel no acute pain, but merely a reluctance to use the limb; and from this, if long continued, the muscles, and afterwards the bones, become wasted. Wasting of the limbs in children, often of one of the lower, frequently arises from disorder of the bowels, and the irritation and debility attendant on teething. This must be distinguished from the wasting accompanying diseased joint. The history of the case, the period at which the weakness of the limb was observed, and its appearance, will lead to a correct diagnosis. The swelling is often irregular, being more protuberant at one part than another, from the fluid or the addition of solid matter being accumulated where the least resistance is afforded; but the slighter inequalities are generally filled up by œdema of the cellular texture. As the disease proceeds, matter forms in the joint, and is often attended with great pain and fever; or the pus is effused into the bursæ, into the surrounding cellular tissue, or into the filamentous tissue amongst the tendinous sheaths of the muscles in the neighbourhood; being allowed to remain without an outlet, it at length communicates with the cavity of the joint. Portions of the cartilages are absorbed, though this, as already noticed, may occur at the very commencement of the disease; the subjacent bone becomes affected by ulceration, or perhaps its vitality is partially destroyed. When matter has accumulated, a portion of the capsular ligament generally ulcerates, the pus escapes, and is ultimately discharged externally.