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years W. A. Bell has consistently dated this flora “Aptian” in reports on
collections made by field officers of the Geological Survey of Canada, and
has recently discussed its age at some length (Bell, 1946). He has also
correlated the Lusear with the Lower Blairmore and Gething floras, con-
sidering them all to be of one age, that is Aptian (the second last stage of
the Lower Cretaceous).

The age of the lower part of the Bullhead group has not been deter-
mined as satisfactorily as that of the upper part. Mathews (1947) has
proposed a late Upper Jurassic or early Lower Cretaceous age for the
lower part of the Bullhead group, that is, for the Monteith, Beattie Peaks,
and Monach formations. J. A. Jeletzky (personal communication)
tentatively suggests a late Upper Jurassic or earliest Lower Cretaceous age for
the Aucella found by Mathews in talus from the upper part of the Monteith
or lower part of the Beattie Peaks formation. He also tentatively pro-
poses an early Lower Creatceous age for fossils collected, in place, by
Mathews from the Beattie Peaks and Monach formations.

No diagnostie fossils have yet been collected from the undivided
Bullhead. No fossils have been collected from the Bullhead group in the
Halfway, Sikanni Chief, and adjacent valleys, and it is not known whether
it represents a part or all of the same group in Peace River and Pine River
Valleys. Nor is it known whether, in disappearing to the north, on Tetsa
and Liard Rivers, this lithological group is replaced there by shale in the
lower part of the Garbutt formation, or whether it thins out and is
unrepresented there by strata of equivalent age.

To the south, in the central Foothills, the Luscar formation, as already
noted, contains the same flora as the Gething, and so is correlative with it.
The lower and marine part of the Bullhead group may be equivalent to
some part of the Nikanassin formation, but no actual evidence exists upon
which to base a correlation. In the southern Foothills, the Gething is
compared with the lower part of the Blairmore on the basis of sharing the
same fossil flora. The typical flora of the Kootenay formation, however,
has not been recognized in the non-marine part of the Bullhead; indeed
little is known of the Kootenay north of Athabasca River. If no beds
equivalent to the Kootenay occur in the Bullhead group, the non-marine
Bullhead may rest disconformably on the marine Monach formation, and
strata of both the Hauterivian and Barremian (mid-Lower Cretaceous)
stages may be missing.

A tentative correlation of the upper part of the Bullhead group,
containing the Gething flora, has been made with the sandstone at the base
of the Cretaceous section in deep wells in lower Peace River Valley
(McLearn, 1945) and with the MeMurray formation on lower Athabasca
River (Stelek, 1941; McLearn, 1945). It may be, too, that the unfossili-
ferous lower part of the Loon River formation on lower Peace River could
be of very early Albian or even of Aptian age and equivalent to part of the
Bullhead, for the Albian (latest Lower Cretaceous) fauna of the Loon River
is confined to the upper part of the formation. These correlations of the
upper part of the Bullhead with beds of more eastern localities, however,
are based mainly on similar lithology, and have not the validity of those
based on similar faunas.