Another complication following the prolonged sojourn of a tracheal tube--rare, it is true--is the development of a mass of granulation-tissue, a veritable tumor, which may occlude the lumen of the trachea and lead to serious disturbances of respiration. The growth usually occurs about the inner edges of the tracheal wound, extending thence inward and upward or downward, as the case may be, and is most frequently met with, perhaps, after tracheotomies undertaken for diphtheria, although it may occur as a result of the ulcerations mentioned above, and develop even from the cicatrix in an old and perfectly-closed tracheotomy wound. The size of the mass, its location, and the amount and manner of its interference with the respiratory current vary much, but the condition must ever be regarded as a troublesome, even dangerous, one, and may always be suspected when attempts at the removal of the canula temporarily or permanently are followed by sudden and urgent dyspnoea. The exuberant granulation-tissue which forms about the outer edges of even a recent tracheotomy wound, and occasionally renders the reintroduction of the tube difficult, as well as closing the wound while it is out, is a much simpler matter, and is easily remedied by cutting it away with the scissors or checking its formation by caustic applications. A subcutaneous emphysema not infrequently occurs as the result of poor surgery and delay at the time of introducing the tube into the windpipe, or may come on later when the tube fits the tracheal wound incompletely. In either case it need excite no apprehension, and usually quickly subsides. Cervical cellulitis is a more serious matter, but is fortunately rare if unconnected with disease of the cartilages of larynx or trachea. It probably depends upon injury to the tissues and a too extensive opening up of the intermuscular strata at the time of the operation. Should the complication arise, the tendency to the burrowing of pus must be prevented by free drainage and, if necessary, incisions. The other surgical indications are to be treated on general principles.