498 Harrison—On the Geology of Hobart Town. 
_ Coal-measure fossils which might have been met with ; but the only 
fossils shown me or spoken of were ferns, and what are called cala- 
mites. ‘There seems among Hobarton geologists a strong desire to 
have their coal-deposits ranked with the English coal-measures ; © 
and any person venturing a statement to the contrary is looked upon 
with disfavour. Yet, notwithstanding this feeling, I could hear no 
hint whatever that either Stigmaria or Sigillaria had ever for cer- 
tainty been found in any of either the shale or the sandstone beds. 
Mr. Wintle’s Séigmaria was probably the stem of some tree-fern, 
which is a very common fossil in the Tasmanian coal-deposits. If I 
am not greatly mistaken, Mr. W. admitted as much to myself in a 
conversation which took place after the paper referred to was posted 
for England. Of this, however, lam by no means certain.—T. H. 
V. Nores oN CHARNWOOD FOREST. 
By D. Macxtntoss, F.G.S. 
1 the midst of a comparatively tame and highly cultivated plain 
of New Red Sandstone near the centreof England, there rises up 
a part of the under crust of the earth which presents so much the 
appearance of an island as to lead the imagination at once to those 
remote ages when its Porphyritic Peaks and Syenitic Knolls were 
surrounded by the sea. The geological history of this celebrated 
spot has been skilfully unravelled by Professors Sedgwick and Jukes 
(Article in Potter’s Charnwood Forest); the Rev. W. H. Coleman 
(Article in White’s Directory); Mr. Edward Hull (Memoirs of Geol. 
Survey); and others. It has lately been invested with additional 
interest by the announcement of the opinion that it is one of the 
“uncovered areas’ or wrecks of the Laurentian or pre-Cambrian con- 
tinents, which Dr. H.B. Holl* and others suppose may have extended 
or may still extend underground, from Scandinavia to Charnwood, 
from Charnwood to the Malvern Hills, and from the latter to’ North 
America. The late Mr. Coleman founded his opinion of their pre- 
Cambrian age on the absence or extreme paucity of organic remains. 
But Dr. Bigsby has well shown that this characteristic would rather 
favour the idea of a formation being posterior to the Laurentian 
(Quart. Journ. Geol. Soc., vol. xix. No. 73); and whatever may be 
the age of the Syenitic Knolls or Bosses of Charnwood Forest, the 
stratigraphical dissimilarity of its slates and porphyries from the Lau- 
rentian formation of America, and their resemblance to the Cambrian 
rocks of North Wales, ought to make us cautious in assigning to 
them a very remote antiquity. In many respects there is not perhaps 
in England a district more puzzling to the geologist than Charnwood 
Forest ; but all agree with Professor Sedgwick in believing its 
* Quart. Journ. Geol. Soc., vol. xxi. No. 81, p. 72. 
+ Apparent traces or impressions of vegetable or animal life have been discovered 
in the Southland slate-quarries on the eastern side of the Forest. 
