Tasmanian Cycadophyta (Part 2.)

In a former paper, read before the Royal Society on 12th May, 1930, I gave some illustrated notes respecting certain cycad stems recovered from the Miocene strata at Evandale. The status of these specimens was called in question by certain palaeobotanists, both in and outside the Australian Commonwealth. By a fortunate discovery a small piece of a trunk was afterwards found that proved beyond all question that they had an organic origin, and were not, as objected, inorganic concretions. This discovery, however, did not extend the microscopical evidence to the concentric woody layers, but related to the inthrusts of periderm into the central cavity of the stem, a state of things already fond to obtain in cycad trunks from Dakota, U.S.A. In September last a splendid section of a trunk was found in the railway ballast-pit, and through the kindness of Mr G. Curtis, of the Railway Department, and the keen interest manifested in it by the actual finder – Mr L.V.Mason – we were enabled to secure this unique specimen. Some 2 feet of the trunk, in three fragments, eventually came to hand, and in many places the structure of the woody rings can be readily studied. As the diameter of the bole is 6 inches by 5 inches, we are evidently in possession of the remains of a fully-grown tree. The finding of this stem sets at rest for ever all objections raised against the organic origin of the specimens, and at the same time supplies us with several connecting links that serve to complete our chain of evidence, as will now be show.