VI.—A Contribution to the Life-History of Bowenia

Abstract

The existing Cycads, with their nine genera and about eighty known species, represent the last lingering survivors of an ancient race that existed in Mesozoic times. There is very little evidence of their geological and geographical distribution throughout that great period; but it seems that up to the close of the Cretaceous they constituted an important feature of the Land Vegetation, with the Bennettitales, Ginkgoales, and Coniferales as their contemporaries. During that long period they were probably represented by many genera and species, and apparently enjoyed a very wide geographical distribution. The nature of their seed as an organ of reproduction seems to have endowed them with great powers of propagation and dissemination, which enabled them to spread over the earth and to occupy dry soils which probably had never before been occupied by Land Plants.