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of Murray Range. The lowest beds are hard, flinty, light bluish grey,
unfossiliferous, massive limestones, weathering to a peculiar honeycomb
texture. These are overlain by thin-bedded, bluish grey, hard, compact,
cryptocrystalline limestone, with inclusions of black chert. Layers of
hard, flinty, limy shale, dense black limestones, and arenaceous limestones
are also present. Williams and Bocock found only fragments of fossils,
but note that Dawson obtained what was possibly a small Athyris. On
this basis, Williams suggests a Devonian age for these beds in Pine River
Valley, and that they are the same as those outcropping high on the east
slope of Wicked River Valley.

Alaska Highway, West of Summit Lake

It has been stated in a preceding paragraph that the lower part of the
beds assigned by Laudon and Chronic to the Ramparts formation is unfossil-
iferous and hence only provisionally included in the Devonian. The upper
part, however, is fossiliferous and of definite Devonian age; it comprises
more than 1,000 feet of limestone, including coral-reef limestone. Williams
(1944) placed these fossiliferous limestones in the upper part of his Silurian
and Devonian unit and noted that they are well exposed in the bed of a
small mountain creek that crosses the Alaska Highway 6 miles west of the
summit. ‘‘About 200 to 300 feet below the top, the limestone is thin-
bedded and mud-cracked into irregular polygons.... The upper limestone
is dark grey and includes coral reefs from which” corals, brachiopods, and
trilobites have been collected. Another fossiliferous zone, in dark grey
limestone, was found near a temporary bridge over Racing River, in which
some corals, brachiopods, and a trilobite were discovered.

Williams states that the fauna collected by him from these fossiliferous
limestones “‘in a general way . . . suggests Middle Devonian faunas of
Mackenzie River’. Laudon and Chronic correlate these Devonian coralline
limestones with the Middle Devonian Ramparts formation of that valley.

The Middle Devonian fossiliferous limestones are overlain discon-
formably by more than 800 feet of soft, black, fissile, pyritic shales, weather-
ing yellow-brown. These black shales were included by Williams in the
lower part of his ‘Devonian and Mississippian’ unit and by Laudon and
Chronic in the Fort Creek formation, on the assumption that this formation
of Mackenzie River Valley extends this far south. They outcrop in the
vicinity of McDonnell Creek and at other places farther west. Near the
base and a few inches above the Middle Devonian limestone, Williams found
Tentaculites spiculus Hall. He proposes a correlation with the Upper
Devonian Chemung formation of New York and with the Minnewanka
formation of the southern (Canadian) Rocky Mountains.

MISSISSIPPIAN
Peace River Valley

The presence of Carboniferous rocks at ‘Fossil Point’ on the north
bank of Peace River, about 3 miles above Rapide-qui-ne-parle-pas,
has been known since Selwyn’s exploration of Peace River in 1875. Wil-
liams and Bocock describe black, well-crystallized limestone with streaks
of calcite at this locality, and list a small fauna, including brachiopods
and corals of Mississippian age.