1008 REPORT—1896. 
Alethopteris and Neuropteris. Hence it is evident that the fronds of these types, 
like some specimens of Sphenopteris, cannot be accepted as true Ferns, but may 
be strongly suspected of belonging to intermediate groups between Ferns and 
Cycads. 
: It is not likely (as has been repeatedly pointed out elsewhere) that any of these 
intermediate forms are really direct ancestors of our existing Cycads, which 
certainly constitute only a small and insignificant remnant of what was once a 
great class, derived, as I think the evidence shows, from fern-like ancestors, 
probably by several lines of descent. 
One of the greatest discoveries in fossil botany was undoubtedly that of the 
Cordaitesee—a fourth family of Gymnosperms, quite distinct from the three now 
existing, though having certain points in common with all of them. They are 
much the most ancient of the four stocks, extending back far into the Devonian. 
Nearly all the wood of Carboniferous age, formerly referred to Conifers under the 
name of Dadozylon or Araucarioxylon, belonged to these plants. Thanks chiefly 
to the brilliant researches of Renault and Grand’ Eury, the structure of these’ fine 
trees is now known with great completeness. The roots and stems have a coniferous 
character, but the latter contain a large, chambered pith different from anything in 
that order. The great simple lanceolate or spatulate leaves, sometimes a yard 
long, were traversed by a number of parallel vascular bundles, each of which has 
the exact structure of a foliar bundlé in existing Cycadez. This type of vascular 
bundle is evidently one of the most ancient and persistent of characters. Both 
the male and female flowers (Cordaianthus) are well preserved in some cases. The 
morphology of the former has not yet been cleared up, but the stamen, consisting 
of an upright filament bearing 2-4 long pollen-sacs at the top, is quite unlike 
anything in Cycades ; a comparison is possible either with Gingko or with the 
Gnetacez. 
In the female flowers—small cones—the axillary ovules appear to have two 
integuments, a character which resembles Gnetaces rather than any other Gymno- 
sperms. Renault’s famous discovery of the prothallus in the pollen-grains of 
Cordaites indicates the persistence of a cryptogamic character; but it cannot be 
said that the group as a whole bears the impress of primitive simplicity, though it 
certainly combines in a remarkable way the characters of the three existing orders 
of the Gymnosperms. 
There is one genus, Poroxylon, fully and admirably investigated by Messrs. 
Bertrand and Renault, which from its perfectly preserved vegetative structure (and 
at present nothing else is known) appears to occupy an intermediate position 
between the Lyginodendrex and the Cordaiter. The anatomy of the stem is 
almost exactly that of Lyginodendron, the resemblance extending to the minutest 
details, while the leaves seem to closely approach those of Cordaites. Poroxylon 
is at present known only from the Upper Carboniferous, so we cannot regard it as 
in any way representing the ancestors of the far more ancient Cordaitew. The 
genus suggests, however, the possibility that the Cordaitee and the Cycadex 
(taking the latter term in its wide sense) may have had a common origin among 
forms belonging to the filicinean stock. It is also possible that the Cordaitex, or 
plants allied to them, may in their turn have given rise to both Conifers and 
Gnetacez. 
It is unfortunate that at present we do not know the fructification of any ot 
the fossil plants which appear to be intermediate between ferns and Gymnosperms. 
Sooner or later the discovery will doubtless be made in some of these forms, and 
most interesting it will be. M. Renault’s Cycadospadix from Autun appears ‘to 
show that very cycad-like fructifications already existed in the later Carboniferous 
period, and numerous isolated seeds point in the same direction, but we do not 
know to what plants they belonged. 
I think we may say that such definite evidence as we already possess decidedly 
points in the direction of the origin of the Gymnosperms generally from plants of 
the Fern series rather than from a lycopodiaceous stock. 
I must say a few words before concluding on the cycad-like fossils which are 
so strikine a feature of mesozoic rocks, although I feel that this is a subject with 
