PROCEEDINGS OF SECTION C. 41} 
normal lower Paleozoic sediments pass into the corrugated fine 
grained mica schists at the foot of the hills, and the mica schists 
up to about 400 feet are characterised by having a preponderance 
of muscovite mica. From that place, which is marked by a mass. 
of diorite, the schists have a different character, being much 
harsher in texture, and having a preponderance of biotite mica. 
Towards the summit of the spur, where the schists are most 
marked, they are clearly recognisable as metamorphosed plutonic 
rocks of the quartz diorite class, which are now in the form of 
diorite-gneisses. 
Further careful work will have to be done before these schists can 
be satisfactorily classed, but for the present I think that these 
mica schists, in which muscovite predominates, may be referred 
to the metamorphosed sediments, while the mica schists with a 
preponderance of biotite and the gneisses belong to the group of 
metamorphosed plutonic rocks. 
On the north-east side of the Omeo district the furthest outlier 
of the crystalline schists is found, between Mount Leinster and 
the Limestone River. I propose to take a section from the 
Limestone River to Marengo Creek, as my second example 
of the supposed passage of the sediments into the crystalline 
schists. 
The section commences at the Limestone River, where there is 
a series of highly-inclined sediments, including a band of crystal- 
line limestone (marble). The age of these sediments is, so far as 
may be judged from the imperfect fossils, of Upper Silurian age. 
The section follows a generally south-westerly course across a high 
range, which forms the divide between the Limestone River and 
the Marengo Creek. If produced further, its course would be 
not far from Mount Leinster, to which I shall again refer 
further on. 
In order to illustrate the section, I shall shortly describe repre- 
sentative samples, giving the approximate distance in chains in a 
direct line from the Limestone River. 
At a distance of about ten chains the sedimentary rocks are 
much hardened and broken up by small joints. The beds dip 
south 40 deg. west at 50 deg. The rock is fine-grained, and under 
the microscope can be seen to be formed principally of innumerable 
minute fibres, of what is probably one of the chlorite minerals. 
Numerous minute veins of quartz granules traverse it, and the 
rock itself has also a large amount of the same granular quartz 
distributed through it. “This quartz is secondary, and not to be 
confounded with the elastic quartz in the rock. 
At about sixty chains these altered sediments are in contact 
with a mass of porphyrite, which extends for nearly fifty chains 
along the course of the section. The sedimentary rocks in contact 
with the porphyrite are hard and flinty, and with the dip and 
strike obliterated. Slices of the rock show it to resemble that 
