1883. ] The Naturalist Brazilian Expedition. 1009 
to S. E., N. W., the dip is generally a slight one to the N. or 
N. E., but sometimes to the S. or S. W.. Thus, in general, the 
strike of these beds also approximates to the trend of the granite 
ridges. 
On the southern flank of the fourth ridge the stratified rocks 
are seen lying directly over the granite; they consist here of 
sandstones, with layers of sandy shale, and two beds of coal, the 
whole dipping S. W. at an angle of about 15°. The side of the 
granite ridge, between the stratified rock, is inclined to the south 
at an angle of nearly 20°. The approximate section, in ascend- 
ing order, is as follows: 
A. Granite. 
B. 1. Coarse sandstone, 30 meters. This rock varies much in 
appearance as it has been more or less weathered. Where it lies 
flat on the hillsides or in the beds of streams, it is reddish or 
_ purplish in color, and very hard, breaking with an angular frac- 
ture. In cliffs, where it has been long exposed to the weather, it 
is white, soft and friable, and worn into curious forms resembling 
statuary. The stratification is irregular, and there are many in- 
stances of false bedding. I suppose that the rock was formed on 
a sea-shore, either in shallow water, exposed to winds and cur- 
rents, or as blown sand in dunes. Towards the top there are 
some layers of sandy shale, not well exposed. 
2. A layer of sandstone, rich in iron, about two meters. 
Where this rock has been long exposed to the weather the sili- 
cious matter has been partly washed away, leaving the iron oxydes 
in concentric layers. These form balls varying from twelve to 
twenty-five centimeters in diameter. By selecting the richest 
Specimens ore may be obtained yielding forty to sixty per cent of 
metallic iron. 
3. Clay conglomerate, two meters. The pebbles are silicious, 
small and irregularly strewn in layers. 
4. Silicious conglomerate, three meters, increasing in fineness 
towards the top and passing into 
5. Coarse reddish sandstone, eight meters. 
6. Red micaceous shale, three meters. 
‘7. Whitish shale, five meters. Probably this was originally a 
dark shale, with much carbonaceous matter, the white color be- 
ing due to weathering. 
8. Coarse sandstone, fifteen meters. 
