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years of age ; the operation for hare lip having been performed during infancy.

The dental arch instead of having the breadth (in comparison with the size of the rest of the head,) of the normal jaw is found to be exceedingly contracted, the two margins of the fissure in the alveolar ridge being very near together, if not in actual contact with each other.

By this time the portion of the palate, that in childhood produced the appearance of a double cleft will have changed its position, and the patient will have that form of palate, which is found in most of these severe cases.

All this is produced, I think, by the contraction of the lip after the operation has been performed on it. The steady pressure which, as the wound heals, is exerted on the two portions of the jaw, gradually approximates the anterior margins of the cleft, and at the same time compels the central portion of the palate to which I have drawn attention, to assume a vertical instead of an horizontal position, as at birth. A careful examination of the drawings in reference to this matter, will I think bear out this view.

For the anatomy of cleft palate I am largely indebted to Sir William Fergusson, who some years back had the rare good fortune to come across a case in the dissecting-room an account of which he gave in a paper read before the