A Bisporangiate sporophyll of Lycopodium lucidulum

A. W. Dupler
1922 Botanical Gazette  
It would seem that the discovery of bodies that have all the megascopic features of sporocarps, that cannot be referred to any other known elements of the associated flora, in association with foliage, which in habit, form, and venation independently suggests comparisons with the genus Marsilea, at two such remote localities as Sweden and western Canada, is strong presumptive proof of relationship. Moreover, these two occurrences are very different in age, thus showing no obvious change in the
more » ... ious change in the sporocarps during the time that elapsed between the Rhaetic and the mid-Cretaceous, a time interval of at least several million years, and comparable in magnitude with the time that has elapsed from the mid-Cretaceous to the present. If these sporocarps preserve their appearance during the older interval, this conservative feature becomes an argument of validity in comparing their latest occurrence with the Marsilea sporocarps of the present. The evidence, then, that Sagenopteris is related to the recent Hydropteraceae is about as conclusive as we can hope to secure in the absence of structural material, which is present in about o.oooi per cent of the cases with which the paleobotanist has to deal.-
doi:10.1086/333104 fatcat:xblxv2fwijgvdpggjike5om2vq