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preserved. At Rose Valley, near Emmaville, tlie vegetable matter has almost entirely 
disappeared, the cast only remaining in the white pipeclay, which is stained a rusty 
yellow where it has received the impressions of the fossils. At Witherden’s tunnel, in 
portion 50, parish of Hamilton, the fossils are enclosed in a dark brown fine sandy clay, 
the original material of the leaf being preserved ; and at the head of the Wellington 
Vale Lead, leaves are similarly preserved in a hardened black silt. A collection of the 
^ fossil plants from Eoso Valley has been sent to Baron von Ettingshausen, and, as already 
stated, they are considered by him to contain many types found in the early Tertiary 
flora of Europe and America ; thus establishing the age of the oldest leads near 
Emmaville as Early Tertiary. Amongst them are several varieties of beech and oak, 
pines allied to the kauri pine, and AVellingtonian pine, intermixed with banksias, 
grevilleas, laurels, and eucalyptus. A detailed list and description is given in Baron 
Ettingshauseu’s work now published. Impressions of fossil insects have been found on 
the Eed Hill, near Emmaville, the markings being plainly visible in fine brown earthy 
ironstone ; but these belong to the later part of the Tertiary volcanic epoch. At a time, 
then, when the physical features of the country were somewhat similar to what they are 
now, and its surface, probably some twenty feet or so higher than at present, was 
covered with an Eocene flora, volcanic energy revealed itself in the first eruptions of 
basalt. The hard rocks of the quartz-porphyry, felstone, and granite were rent 
open; and, where the volcanic forces became centralised, small cones were thrown 
up composed of comminuted fragments of the underlying rock and scoriaceous 
basalt. The lava emanating from these centres poured into the valleys in 
streams from one hundred to two hundred feet thick, flowing for a distance 
of from six to twelve miles. Dispossessed of their old beds, the creeks and 
rivers bad to wear for themselves fre.sh channels, either down the centre of the 
lava stream, or along one or both of its margins. It is probable that, in accordance 
with facts observed in connection with recent lava streams, the sides of these old basalt 
flows in contact with the cold rim-rocks would cool and consolidate while the centre of 
the mass was still fluid. The result of this would be that the centre of the stream would 
flow away from the sides leaving them at a higher level, and so giving rise to a slight 
central depression. This would favour the erosion of the new channel immediately over 
the site of the old one, where the lava must necessarily have been thickest and so most 
fluid, and where consequently the lowest point of the depression should lie theoretically. 
More frequently, however, the water chose the junction lines of the basalt with the 
Palffiozoic rocks. That the volcanic activity was prolonged for a vast space of time 
is . proved by the extent of denundation which has taken place between the older 
flows of lava and the newer. The amount of this can be measured at the upper end of 
the Vegetable Creek Lead at Eose Valley. The section at Griffith’s and Fox’s shafts 
shows that a watercourse has cut through one or more flows of basalt altogether 
to a depth of about sixty feet. Then succeeded another flow of basalt, which buried the 
second channel to a depth of a hundred feet. These second eruptions appear to have 
been less violent than the first, the lava welling up, probably from wide rents, and 
producing the low, gently sloping cones of solid lava, destitute of the volcanic dust and 
scoria characteristic of the earlier outbursts. Evidence as to which is the latest flow 
of basalt is rather meagre ; but judging from the general freshness of the appearance of 
the lava at Kangaroo Flat, in Portions 70 and 73, Parish of Arvid, it seems to me that 
this flow is one of the most recent. Powerful streams must have flowed in places over 
the surface of the basalt long after its consolidation, as evidenced by the coarse Pliocene 
gravel in Portions 696 and 751, Parish of Strathbogie, where some of the water-worn 
blocks are over one foot in diameter. This gravel is, roughly, about one hundred and 
