_c._ Bruising of the edges from careless sponging, or rough manipulation with clumsy instruments. This is particularly liable to occur if the edges are pared prior to the detachment of the muco-periosteal flaps, in accordance with the mistaken directions given in many text-books. _d._ Inaccurate coaptation of the edges of the wound, caused either by the stitches not being inserted at exactly opposite points on either side of the cleft, or by bringing the edges together too loosely, or so tightly that they are curled in. _e._ Incomplete division of the levator palati will possibly explain some cases of non-union of the soft palate. _f._ Want of careful supervision after the operation, and unsuitable food. _g._ The occasional occurrence of uncontrollable vomiting or excessive hæmorrhage. The most frequent situation of defective union is at the point of junction of the hard and soft palate; the tissue here is extremely thin, and laceration is liable to occur during the detaching process. The apex of the cleft is another likely spot where union may fail; here from rigidity of the tissues accurate apposition is rendered difficult and sometimes impossible, particularly when the deformity is associated with alveolar cleft. When apertures have resulted from any of the above detailed causes, it is useless to attempt to close them immediately, and moreover subsequent cicatrisation may much diminish their size or even close them entirely. M. Trélat[94] has seen one 9 mm. in diameter thus disappear, and my experience fully confirms such an observation. When, however, the contraction has come to a standstill, the margins may be pared, the lateral apertures reopened, the tissues loosened again from the bone, and the opening closed by as many sutures as may be necessary. Small fistulæ are often cured by the application of lunar caustic or fuming nitric acid. Occasionally some trouble is experienced in the closure of the lateral apertures, one or both of them remaining patent and threatening to become fistulous. As a rule no anxiety need be entertained on this score. The only case in which I have had trouble was in a severe complete cleft in a young woman of twenty-seven; one of the openings was only closed twelve months after operation by applying nitric acid.