GEOLOGY OF NORTH GIPPSLAND, VICTORIA. 13 
gatta, the Wongungarra, and the Crooked rivers and their subsidiary 
streams. On the western side of the Dargo-River valley, on the 
line of section, the Silurian strata are exhibited as greenish and 
bluish clay-slates, alternating with quartzose or micaceous sand- 
stones, and having a strike to the north-west and a dip of from 70° 
to 80° to the north-east. On crossing the Dargo River at Mayford, 
the hillside shows bluish clay-slates of the same direction of strike 
and dip, but having a somewhat crumpled silky appearance. On 
ascending the steep eastern side of the valley a gradual change is 
met with from these last-named rocks, through finely micaceous 
schists to gneiss. 
Although these schists are in places much crumpled and contorted, 
it is still possible to see that the foliations of the various beds, and 
the beds themselves, conform to the direction of the strike and dip 
of the Silurian clay-slates ; and it is important to bear in mind that 
the dip of the clay-slates, and of the mica-schists into which they 
seem to pass, is to the north-east, and therefore underneath the 
more highly altered schists at the summit of the hill. The slope of 
the ascent is great, and in so far is favourable to observation as re- 
sembling a cliff-section. The vertical height from the clay-slates of 
the river to the gneiss at the summit is 1350 feet, and the horizontal 
distance about from 80 to 100 chains. 
This summit is the Great Dividing Range, and from this point 
there is gently undulating country to within about two miles of the 
Omeo township. Throughout this distance the following rocks 
alternate :—Gneiss and gneissoid mica-schist, schistose granite, 
granites of binary, ternary, and quaternary composition, consisting 
of orthoclase and quartz, orthoclase, quartz, and mica (principally 
black), or the three together with black and greenish-black horn- 
blende. 
It is to be remarked that so soon as the schists, in ascending from 
the Dargo River, become more siliceous, irregular patches or veins 
of slightly translucent and somewhat greasy-looking quartz appear, 
forming part and parcel of the foliations. More rarely, veins are 
met with of coarsely aggregated orthoclase, quartz, silvery mica, and 
often black schorl, and these are usually associated with the granite 
schists or the granites (metamorphic). 
Other veins are also to be met with of orthoclase, quartz, and 
fibrolite, ali confusedly aggregated together. The fibrolite in places 
shows certain resemblances in colour and in imperfect prismatic 
forms to andalusite and even to kyanite. It is found of pale tints 
of lilac, blue, pink, as well as white, and is exceedingly tough in 
texture. 
The granites are usually met with in the low grounds, in the 
valleys, but also as small plains at higher elevations. In fact, 
granites belonging to this division are met with in this locality at 
all heights, but more generally, as I have said, where streams have 
cut deep into the schist surface. 
In the schists and granites, speaking generally of the whole 
series, we meet with numerous intrusive dykes, from a few inches 
