Ester Wax i960: a Histological Embedding Medium

retains the softness of infiltrated tissues. 2. The section, both wax and specimen, flattens on water. 3. The sections of a ribbon adhere during flattening. 4. Adhesion of sections to the slide is good. 5. The room temperature for successful ribboning may vary from 170 to 250 C or higher. THE softness of infiltrated tissues when diethylene glycol distearate isthe infiltration medium has been the subject of favourable comment by Orton and Post (1932), Cutler (1935), Steedman (1947), Chesterman and Leach (1956), and others. The considerable hardness of this material com-pared with paraffin wax and its slightly lower melting-point (48°C) constitute additional attractive features which have induced research workers to give it most thorough examination. Alone, diethylene glycol distearate has weak-nesses which preclude its use as an infiltration medium. The 1947 (Steedman) formula produced a medium of excellent ribboning properties, but gave poor flattening of sections, and showed separation of the sections of a ribbo