THE GEELONG NATURALIST. 
11 
rocks of the middle Tertiary period constitute the surface formation 
of various small areas in the G-eelong district, around Melbourne, 
near Bacchus Marsh, Ballanand between Lethbridge and Steiglitz," 
and this volcanic sheet is continuous from Lethbridge to Connewarre 
Lakes, with the exception of a few breaks, and these breaks are filled 
up with Pliocene drift. Some of them having Pliocene animals' 
bones, others gravels mixed with pieces of slate and mudstone, and 
carrying a small amount of gold and classed by Mr Selwyn as 
Pliocene. When we consider the above facts, I think we can rest 
satisfied that the age of the basalt which is so plentiful about 
Oeelong is Miocene. 
The basalt at the south side of the Moorabool between the 
Paper Mill and Dog Eocks, appears to be of more recent age than 
that before mentioned. It is probably of Pliocene or Pleistocene 
age. There is no doubt it extends the whole distance between those 
two places in a thin sheet. Although most of this is now decomposed, 
leaving nothing but ironstone pebbles in patches, it still exists as 
basalt. This is on a different level altogether to that on the north 
side of the river It also overlies the gravel bed which I take to 
be Pliocene if not younger. This is proved by a waterhole near the 
school, and the shaft sunk near the Dog Rocks. The centre of 
volcanic activity at this time appears to have been about Pyansford. 
Several crater like basins are still to be seen there, and a granite tor, 
some tons in weight, is lying near the Starch Mills. Most likely 
this was blown up at the time of the output, for there is no granite 
nearer than the Dog Rocks, some miles distant. 
EXCURSION TO SHELFORD. 
This excursion took place on Monday, the 11th November. The 
principal object being to inspect a certain formation, which at 
present is a much discussed question, in regard to its geological 
age. A thoroughly representative party filled a large drag, and 
with a splendid team of four, left Greelong at 5.30 a.m., and covered 
the distance to Shelford via Leigh Road, punctually by 9 o'clock. 
By previous invitation, the party was sumptuously entertained 
at breakfast at G-olf Hill. Miss Russell, Miss Carstairs, Messrs 
Bell and the Rev. H. M. Burn, M.A., B.D., were unremitting in 
their efforts to promote the comfort, and add to the pleasure of every 
member, who fully endorsed the vote of thanks so ably put by Mr. 
<T. H. Adcock, F.L.S., one of the vice-presidents. After breakfast 
the whole of the noble estate was freely placed at the disposal of the 
members by the courteous proprietor. A visit was then paid to 
«ome of the romantic Grorges, a few miles up the river, where the 
Silurian formations were inspected, and several specimens obtained. 
Here Mr. Swan, of Shelford, was met with, and not a few of the 
ardent, but wearied collectors, will gratefully remember this 
.gentleman's kindness in placing his buggy at their disposal. Some 
