86 Palaeontologie. 
the pinna trace cannot however be followed in the single section 
described. 
The section is compared with Zygopteris duplex (Will.) and 
especially with Dineuron ellipticum Ren. 
The stem Stele of Botryopteris antiqua sp. nova. is very small in 
comparison with the petioles. The stem has an irregulär form, owing 
to the departure of petioles and roots. The cortex is formed of thick- 
walled prosenchymatous cells of small diameter, and without inter¬ 
cellular spaces. The outer surface of the stem bears numerous hairs, 
formed of a single row of cells. 
The stem Stele is circular, and consists of very small tracheae, 
without parenchyma. The protoxylems are not distinguishable, nor 
can the departure of the leaf-traces be followed. 
The petioles are apparently given off spirally. The cortex forms 
a broad zone of thick-walled prosenchyma, bounded internally by 
an endodermis. The soft elements of the leaftrace are not preserved. 
The xylem is oval, and slightly flattened on one side. The scalariform 
protoxylem elements occur on the more pointed or adaxial side, 
their distribution being very irregulär. There are no protoxylem 
teeth. The metaxylem of the leaf trace consists of large tracheae 
with porose walls, arranged without any definite Order. The petioles 
underwent bifurcation. The pinnae appear to have been alternate, 
and their traces arise as small protuberances on the trace of the 
petiole. The roots, arising directly from the xylem of the stem, are 
very small and diarch. 
Botryopteris antiqua, which is perhaps the smallest member 
of the genus, is compared with other species from the Upper 
Carboniferous. Arber (Cambridge;. 
Kidston, R. and D. T. Gwynne-Vaughan. On the Fossil 
Osmundaceae. Part. II. Zalesskya gracilis Eichwald sp. and 
Zalesskya diploxylon Kidston and Gwynne Vaughan n. sp. 
(Trans. Roy. Soc. Edinburgh Vol. XLVI, Part II, No. 9. p. 213—232 
with 4 plates, 1908.) 
In this memoir two species, one of them new, both referred to a 
new genus Zalesskya, are described from the Thuringien (Zech¬ 
stein) of the Oural, Russia, from specimens preserved in the 
Museum of the Institute of Mines, St. Petersburg. The first 
species has been previously discussed and figured by Eichwald 
in ‘Lethaea Rossica 1 as Chelepteris gracilis. 
The paper commences with a consideration of the relationship 
and distinctive characters of Chelepteris, Sphallopteris, Bathypteris 
and Anomorrhoea as defined by Corda or Eichwald, and in- 
cluded in the group Protopterideae. Reasons are given for the 
removal of the Chelepteris gracilis of Eichwald to a new genus, 
Zalesskya, to separate it from those species originally placed by 
Corda in Chelepteris . 
Zalesskya gracilis possessed a very wide Stele, surrounded by an 
even wider, thin-walled cortex, which possessed a narrow external 
border of thick-walled elements. The preservation is excellent. The 
cortex is traversed on all sides by a very large number of departing 
leaf-traces, which arose from the stele in a close spiral. Roots also 
occur here and there. 
The xylem of the stele forms a broad and perfectly continuous 
ring, surrounding a central empty space. It is composed of tracheides 
