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geologists studying the Mesozoic that many correlations based on litho-
logical resemblances alone have been unreliable, and that they have been
revised when faunal evidence has become available.

__ Three and possibly four macrofaunas are known, and furnish faunal
evidence for correlation. The three well-defined faunas are, in descending
order:

Neogastroplites fauna
Gastroplites fauna
Lemuroceras or Beudanticeras affine fauna

The Lemuroceras fauna, as recorded in previous paragraphs, carries species
of the genus Lemuroceras, and Beudanticeras affine (Whiteaves), and some
pelecypods. The Gastroplites fauna includes species of Gastroplites and
Inoceramus, and some starfish. The Neogastroplites fauna has species of
Neogastroplites, Posidonomya, and Oxytoma. It is possible, but far from
proved, that a fourth ammonoid zone lies between the Gastroplites and
Neogastroplites zones. It contains crushed specimens of an ammonoid
difficult to identify generically. Specimens collected by McConnell on
Liard River were described by Whiteaves (1892) and given the name of
Placenticeras liardense, and may represent a younger ammonoid genus than
Gastroplites.

The Lemuroceras fauna is found in the Moosebar and Gates formations
on Peace River, and permits a faunal correlation of these strata with a
lower part of the Buckinghorse formation on Sikanni Chief River. The
Gastroplites fauna has been reported from the upper part of the Commotion
formation on Pine River, and makes possible a correlation of that part with
a lower part of the Hasler formation on Peace River and an upper part of
the Scatter formation and lower part of the Lépine on Liard River. The
Neogastroplites or Posidonomya nahwisi fauna in the Goodrich formation
on Pine and Peace Rivers correlates that formation with the lower and
sandstone-bearing part of the Sikanni formation on Sikanni Chief River;
the middle sandstone in Tetsa River Valley; a part of the ‘fissile shale’ on
Petitot River; and shales high in the ‘Shaftesbury’ formation east of Cache
Creek on Peace River.

The correlations, considered in the foregoing paragraph and based on
faunal evidence, afford a strong supporting framework for the remaining
correlations, which, unfortunately, must rest on the weaker lithological
evidence. Because of similar lithology and similar stratigraphic position
the Moosebar shale on Pine River is correlated with the Moosebar on Peace
River. The claim made by students of the Pine River section that the
Commotion formation on Pine River is equivalent to the Gates plus a
lower part of the Hasler formation on Peace River is a reasonable one, for
it has already been demonstrated that faunal evidence supports a correla-
tion of the upper part of the Commotion with the lower part of the Hasler
formation, and the evidence of similar lithology supports a correlation of
the lower part of the Commotion formation with the Gates.

On lithological evidence, Allan and Stelck (1940) compare the Moosebar
’ shales and Gates sandstone with similar shales and sandstones in the No. 1
Guardian well near Bonanza, Alberta, just east of the area included in this

report.