with considerable quantities of dark mica, and green hornblende. In
one of the specimens the quantity of free quartz is so small that the
rock is almost a quartz-free diorite. The quartz diorites are: some
medium-grained, some coarse-grained (quartz-diorite-pegmatite), with
streaks of black mica. The schistose rocks from Scott's Nunatak are
streaked, and, in part, very fine-grained quartz diorite schists. Mica
schists do not occur among the specimens from this mountain.

Our knowledge of the geology of South Victoria Land is mainly due to
Scott's expedition of 1901 -- 1904, with H. T. Ferrar as geologist,
and Shackleton's expedition of 1907 -- 08, with Professor David
and R. Priestley as geologists. According to the investigations of
these expeditions, South Victoria Land consists of a vast, ancient
complex of crystalline schists and granitic rocks, large extents
of which are covered by a sandstone formation ("Beacon Sandstone,"
Ferrar), on the whole horizontally bedded, which is at least 1,500 feet
thick, and in which Shackleton found seams of coal and fossil wood (a
coniferous tree). This, as it belongs to the Upper Devonian or Lower
Carboniferous, determines a lower limit for the age of the sandstone
formation. Shackleton also found in lat. 85deg. 15' S. beds of limestone,
which he regards as underlying and being older than the sandstone. In
the limestone, which is also on the whole horizontally bedded,
only radiolaria have been found. The limestone is probably of older
Palaeozoic age (? Silurian). It is, therefore, tolerably certain that
the underlying older formation of gneisses, crystalline schists and
granites, etc., is of Archaean age, and belongs to the foundation rocks.

Volcanic rocks are only found along the coast of Ross Sea and on
a range of islands parallel to the coast. Shackleton did not find
volcanic rocks on his ascent from the Barrier on his route towards