Foerstiaand recent interpretations of early, vascular land plants

Abstract

Schopf, James M. 1978 04 15: Foerstia and recent interpretations of early, vascular land plants Foerstia should be regarded as a marine fucoid, contrary to the recent interpretation of Gray and Boucot who relate these fossils to land plants. Although the megaspore coats are resistant and may be waxy, the thallus lacks cuticle and it has internal filamentous tissue like Fucus and other fucoidal algae. The megaspores, borne in fucoidal conceptacles, are unusual and may be forerunners of the more reduced oocytes that occur in modern Fucales. Detailed illustrations are provided. There is no evidence that these plants have ever been anything but marine. Likewise, tubular microfossils that show internal thickenings and occur in Ordovician and Silurian marine deposits should not be designated ‘tracheid-like’, as done by Gray and Boucot, because it is unlikely they represent land plants or function in conduction. They show a surprisingly consistent association with Chitinozoa. They illustrate the adage that structures identified simply by their form may be of diverse origin. Neither Foersria nor the annulate tubules are relevant to the origin of temestrial vegetation.