American Fossil Cycads ¹

Abstract

THE wonderful state of preservation of many Pa1æozoic plants, which has enabled us to gain much valuable information in regard to phylogenetic problems, is in marked contrast to the general absence of petrified fossils afforded by Mesozoic strata. Thanks to the ability and energy of Mr. G. R, Wieland, liberally backed by the Carnegie Institution, a flood of light has been thrown on the morphology of an extinct group of Mesozoic gymnosperms, which it is possible to study with a precision and thoroughness hardly to be surpassed in the case of recent plants. Mr. Wieland's monograph, with its splendid set of large plates, is an addition to botanical literature of exceptional importance. After reading the volume, we couple with a grateful acknowledgment of what has already been done an earnest wish that the results of further investigations may be presented in an equally attractive form in the near future.