=Instruments.= Beer’s knife, fixation forceps, lid clamp (Fig. 145), spatula, and sutures with a glass bead threaded on each. =Operation.= The operation is performed under a general anæsthetic. _First step._ The lid is fixed in a clamp. The surgeon makes an incision in the skin directly above the lash-bearing area throughout the whole length of the lid and parallel to its margin. A second incision is made about 3 millimetres above this, and its extremities are curved downwards to join the first. The piece of skin and orbicularis muscle between them is removed and the tarsal cartilage is exposed. _Second step._ A wedge-shaped strip is removed from the tarsal cartilage throughout the whole length of the lid, the apex of the wedge reaching just through the cartilage, but not the conjunctiva on its under surface. _Third step._ Mattress sutures are then inserted. Each suture should have a needle at either end. A bead may be threaded on the stitch to prevent it cutting into the lid margin. The needles are passed from the margin of the lid directly above the eyelashes, about 3 millimetres apart, and brought out through the lower margin of the wound. They are then passed from within outwards through the tarsal plate and the upper margin of the wound, being brought out through the skin about half an inch above it and tied (Fig. 146). A few points of suture in the skin may be added if necessary. [Illustration: FIG. 147. ARLT’S OPERATION FOR TRICHIASIS.] THE TRANSPLANTATION OF THE LASH-BEARING AREA =Arlt’s operation.= =Indications.= The operation is suitable for cases of trichiasis in which part or the whole of the lashes of the upper lid turn inwards and rub on the surface of the cornea. =Instruments.= Beer’s knife, forceps, scissors, sutures, lid clamp. =Operation.= _First step._ A lid clamp is applied to the upper lid. An incision is made in the intermarginal line and the tarsal cartilage is split behind the lash-bearing area for a depth of about 5 millimetres throughout the whole extent of the lid (Fig. 147). _Second step._ An incision through the outer surface of the lid above the lashes is made to meet the other at right angles, so that the lashes are carried on a band of tissue attached at each end.