33 
\ 
slightly prominent, straight, and, towards the apex, gradually narrowed 
midrib, and remarkably thin, acute-angled, simple secondary veins, 6-7 on 
each side, proceeding almost directly towards the teeth. The tertiary veins 
proceed on both sides of the secondaries at right angles ; they are very fine 
and short, and merge immediately into a very fine net, composed of almost 
rectangular, oblong meshes. (Compare the enlargement of the venation in 
Fig. 1 a.) 
The described beech leaf, as regards its characters, occupies an inter- 
mediate position between the Fa (jus prise a, Ett., of the Cretaceous Flora, and 
the Miocene Fa jus Feronice , Ung. In its generally simple dentation and 
the coriaceous texture, it reminds us of the former but in its venation of the 
latter; whilst the form of its leaves, the arrangement of the marginal teeth, 
and the small number of its secondary veins arc common to both. Me may, 
therefore, regard F. Wilkinsoni as a species whose leaves in several of 
their characters still represent the beech of the Cretaceous Epoch, but which, 
as regards their most important character, that of the venation, already 
announce a beech of the Mioconc Period. The F. Wtlkinsoni, nevertheless, 
possesses peculiar characters, by which it is distinguished from both of the 
beeches named, more especially the tine secondary veins, and the very short 
immediately anastomosing tertiary veins. In addition to this, the obtuseness 
of the teeth, which gives an almost undulate appearance to the margin, con- 
stitutes a peculiarity in our species. From these facts it may be concluded 
that Fagus Wtlkinsoni forms an independent link in the chain of evo- 
lution of the beeches, and also that this link, as regards time, belongs to a 
period intervening between that of the Cretaceous and Miocene species, or 
the Eocene Period. 
I have found it exceedingly interesting to compare the leaves of Fagus 
Wtlkinsoni with the leaves of still existing Australian beeches. There arc 
three species of the genus Fagus now living in Australia. F. Moorei, F. 
Muell., represents, as regards the form of the leaf, to some extent the North 
American F. ferruginea, Ait., but has thick coriaceous leaves. The latter 
are ovate or lanceolate, acuminate ; the margin of the leaves and the venation 
are quite like those of F. ferruginea. In one leaf of a specimen of the F. 
Moorei, in the 11 oval Herbarium at Kew, I observed an indication of 
the double indentation of the margin. In the same place I found on a 
smaller leaved branch of this species all the leaves doubly dentate in this 
manner, and between the teeth at the extremities of the secondary veins 
lire 67— ss g 
