Modifications of the transfer technique for studying complex plant structures

Abstract

The transfer technique is a method for exposing compression fossils that entails embedding the specimen in an adhesive material and dissolving the matrix in appropriate acids. This technique has been used for many years, and played an important role in several classic paleobotanical studies. However, in recent years it appears to have fallen into relative disuse and is not discussed at all in recent compilations of paleobotanical techniques. This is unfortunate, as the method is often extremely effective, especially for revealing the detailed structure of complex plant organs. In this paper, case studies using fossil conifer ovulate cones are presented. The first entails a modification of the classic transfer technique using a polyester resin as the embedding medium on an unnamed cone from the Triassic of Pennsylvania. The second study entails producing serial sections through a polyester resin embedded cone of Telemachus from the Triassic of Antarctica in a manner analogous to the classic cellulose acetate peel method. This modification is most useful when the organic material is too fragile for the more classic method. The results of these case studies are presented in the hope of re-stimulating use of the transfer technique in paleobotany. © 2009 Elsevier B.V. All rights reserved.