One of the most striking results of palæobotanical research has been the discovery that in Palæozoic times a class of Vascular Cryptogams existed, quite distinct from any of the three main groups of Pteridophyta with which we are familiar in the recent flora. This class, the Sphenophyllales, while showing in certain respects a clear affinity with the Equisetales, in other characters rather approaches the Lycopods, and some botanists have endeavoured to trace a relation to the Ferns. The work of the last few years has pointed to a connection between this extinct group and the recent Psilotacese; some authors have gone so far as to include the latter in the Sphenophyllales. So far as fossil members are concerned, the class is represented by two genera only—the extensive and comparatively well-known genus
Sphenophyllum
, ranging from Devonian to Permian, or, perhaps, Triassic times, and the more recently discovered
Cheirostrobus
from the Lower Carboniferous, of which only the fructification is at present known. Each of these genera must be regarded as representing a distinct family within the class.
Spheuophyllum
, indeed, is a “genus” only in name, embracing, if we judge by the fructification, several types of generic value. The object of the present communication is to describe a newly discovered fossil strobilus, clearly belonging to the family Sphenophylleæ, but presenting new features of considerable importance.