Double embedding broad thin leaves in paraffin.
Paraffin pellets were melted in 24x24x5 mm stainless steel base molds. Specimens of leaves, 18x18 mm, were fixed, dehydrated and infiltrated with paraffin. Two specimens were transferred into molten paraffin on their laminar surfaces in a base mold and moved quickly onto a cold surface to cast them in a shallow block of paraffin. Each block was then scored with a razor blade, broken into two primary blocks, and trimmed to 20x9 mm with 5 mm flat edges. Each primary block was immersed upright on its long edge in a 22x22x20 mm Peel-A-Way embedding mold containing molten paraffin. The leaf edge was held centrally in the mold while moving the double embedment onto a cold surface. In this secondary block, the leaf specimen stood perpendicular to the sectioning surface in perfect orientation for transverse ribbon sectioning. The two phases of paraffin bonded well.
Graham
E T
ET
Department of Ornamental Horticulture, Agricultural Experiment Station, The University of Tennessee, Knoxville 37901-1071, USA.
D006652:Histological Techniques / Q000295:instrumentation; D016612:Paraffin Embedding / Q000379:methods*; D018515:Plant Leaves / Q000166:cytology*