SOME convenient glass micro-forceps are shown in Fig. 1. Type I are opened by their own resilience and closed by means of a tube fitting around them. In type II the reverse action is shown, closing being effected by resilience and opening by the force of a ball and rod. The two branches of the forceps are fixed in a tube of 1.5 mm. diameter, which is mounted on a de Fonbrune micromanipulator. A second tube, enclosing the first tube, can be made to slide around the branches of the forceps, operating it by means of a piston and a syringe. The closing movement is smooth and can be controlled within the limits of a few microns. The points remain exactly opposed.