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DESCRIPTIONS OF NEW SPECIES OF FOSSIL 
LEAVES FROM THE TERTIARY DEPOSITS OF 
MOUNT BISCHOFF BELONGING TO THE GENERA 
EUCALYPTUS, LAURUS, QUERCUS, CYCADITES, 
Etc. 
Br Rost. M. Jounston, F.L:S. 
[Read June 9, 1885.] 
To Mr. Sprent, who is now taking a very active part in arous- 
ing the interest of Surveyors, and others throughout the 
island, in all matters connected with local geology, I am 
indebted for the opportunity afforded me for the examination 
of a very valuable collection of Fossil Leaf impressions 
collected by Mr. Kayser, the very able manager of the 
Mount Bischoff Tin Mining Company’s works at Mount 
Bischoff. The fossil impressions are very numerous and 
well defined, in a somewhat greyish sandstone, whose position, 
I learn from Mr. Kayser, underlies that recent basaltic sheet, 
which, with associated tuffs, occupies a considerable portion 
of the country in and around Mount Bischoff, and also 
extends more or less uninterruptedly over a considerable 
portion of the Surrey and Hampshire Hills, and towards Hmu 
Bay, where a fine exposed headland exhibits basaltic columns, 
remarkable for their prismatic form and regularity. These 
tertiary beds repose upon or flank the tin-bearing eurite 
porphyries and the older associated slates, which, with their 
detritus, form the principal elevated boss of Mount Bischoff. 
The mount in itself is not very conspicuous at a distance, as 
it rises from the great elevated undulating plateau, stretching 
throughout a very considerable portion of the west and 
north-west part of the island. The level of this plateau 
maintains a general altitude above the sea of from 1,500 to 
to 2,000 feet all along the western flanks of the greater inland 
greenstone plateau of the Lake Country, and for a consider- 
able extent towards the northern and western coast line, 
towards which it ultimately slopes more or less gradually. 
The leaf beds at Mount Bischoff, therefore, are at a very 
much higher level than those with which we are already 
familiar in the Tamar and Derwent Basins, which latter range 
in altitude from sea level to 600 feet. The collection made 
by Mr. Kayser is a very interesting one, as not only do all 
the forms discovered appear to belong to new species, but in 
some cases to genera not before discovered fossil in Tasmania. 
The prevailing form appears to be a species of Oak, allied to 
Quercus drymejoides HKttingshausen, found at Dalton, near 
Gunning, New South Wales. One of the most striking and 
beautiful forms, however, is a species of Laurus, 7 inches 
long and 2 inches wide, which I have described and named 
L. Sprentii, in honour of Mr. C. Sprent, Deputy Surveyor- 
