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bituminous odour when rubbed together or struck with the
hammer. On seams and on bedding planes black, hardened
bituminous matter is frequently found, also in gash veins of
calcite which intersect the rocks. Actual seepages of oil have
not been observed from these rocks, nor from any rocks in the
Maude formation.

Microscopically they are seen to consist of alternate laminz
made up of grains of varying sizes and of different materials.
The calcareous bands are composed of equidimensional calcite
grains with ragged outlines, as if secondary calcite had been
added to them, in a matrix of fine fresh plagioclase and other,
finer detritus, in part not resolved by the microscope. Pyrite
occurs in minute, rounded, concretionary replacements, and
brownish bituminous matter is found between the grains.

The finer bands are more argillaceous, containing fragments
of oligoclase, Ab7;An; to andesine AbgpAna in a very fine matrix,
also bituminous. A little muscovite is developed, but sparingly.

These rocks are extremely dense, but the alteration is the
result of induration by pressure alone, with little or no shearing,
and little high temperature action.

Tufaceous Sediments. In places and especially near the top
of the formation, the rocks are more thickly bedded, coarser, and
tufaceous in appearance. Various shades of dark grey and green
occur, and the textures vary from fine even grained, to rather
coarse, unevenly fragmental. The rocks are made up of frag-
ments of various basic effusive volcanics, feldspar, etc., and are
usually more or less calcareous.

In thin section they vary considerably, and are greatly
replaced by calcite, but originally they consisted of fragments
of basalt and andesite porphyrites in a tufaceous matrix, with
fragments of feldspar, augite, etc. Many of the porphyrites
are completely replaced by granular calcite, even the albite
twinning and zonal growths in the plagioclase being faithfully
preserved. Chlorite in matted granular areas, and as pseudo-
morphs after augite commonly occurs, and also large amounts
of limonite.

Slaty or Shaly Argillites. These rocks, the most highly
fossiliferous of the formation, are black, carbonaceous, paper-