found near Hobart Town, and Launceston. 
135 
The sandstone is from “ Spode’s” quarry, and from a well in 
“ Marshall’s” garden, a distance of 100 to 200 yards on either 
hand. 
The shale crops out in thin laminae; has a direction nearly 
east and west, and dips to the southward at an angle of about 
20° to 25°, alternating on either hand with a more compact 
schistose clay, and passing on one side into a granular grauwacke- 
like rock, and the fine white even sandstone of Marshall’s garden, 
and on the other, into the more carbonaceous and less even¬ 
grained sandstone of Spode’s quarry. 
These fossil impressions, which are chiefly of ferns, and dis¬ 
played with a delicacy and hardness of outline rarely seen, abound 
most where the slatey character is most perfect. By a sort of 
natural electrotype process the vegetable matter has been replaced 
by oxide of iron, fixing with a fidelity scarcely conceivable the 
most slender ramifications and gossamer-like veins. In some, for 
instance, the traces of fructification are preserved. 
All these ferns branch repeatedly; and it lias been remarked 
that the angle of divergence is, as compared with that of the exist¬ 
ing members of the tribe, exceedingly acute. In the fine-grained 
shale the profusion and interlacing of the fossil contents is often 
such as to render almost indistinguishable individual forms. The 
difficulty of discrimination and identification is rendered still 
greater, by the natural tendency of all ferns to depart, more 
or less, in the developement of their minuter parts, from the 
established type of their respective species. I shall not therefore 
attempt any exact definition, but merely set down, as rough land¬ 
marks in further enquiries, a few prominent and palpable pecu¬ 
liarities of the most striking of these forms, in the order in which 
they present themselves. 
A fern, probably an Odontopteris, and perhaps the same 
as figured by Strzelecki, tab. vi. fig. 4. The leaflets are long 
and narrow, and rounded at the apex. They form an acute 
angle with the rachis on which they are set alternately. 
A narrow-stemmed slender plant, chiefly bifurcate without 
leaves, probably a fern akin to Sphenopteris Bifida, which, 
according to Bindley, is met with in the mountain limestone at 
