42

Whitesail Lake Map-Area

W. A. Bell of the Geological Survey examined the plant collection and

reports:

Most of the plant remains are too fragmentary to be of value. The few complete
or nearly complete leaves show, at best, only the primary and secondary nervation
and hence even a generic identification is open to question. With this reservation
the leaves are referred to the following.

Alnus sp.
Rhamnites marginatus ? (Lesquereux )
Spirodela ? scutatata ? Dawson

The doubtful nature of the above identifications precludes any confident con-
clusion on precise age represented. So far as the evidence goes a late Upper
Cretaceous or Paleocene age is considered probable.

E. T. Tozer of the Paleontological Division of the Geological Survey

examined the shells in the collection and reports:
Catalogue No. 17180

Unionid genus indet.
Sphaerium sp. (cf. S. heskethense Warren)
Lioplacodes sp. (cf. L. sanctamariensis (Russell) )

Although this faunule is very rich in individuals it is poor in species and
consequently a satisfactory comparison with other faunas cannot be made. No
significance can be attached to the unionid but some of the sphaeriids have
the prominent posteriorly placed umbones characteristic of the Edmonton (Upper
Cretaceous) species S. heskethense Warren. The Lioplacodes is closer to
L. sanctamariensis (Russell), a contemporary of S. heskethense, than to any
other described species. Although the faunule does not permit an unequivocal
correlation an Upper Cretaceous age is suggested.

Near Tchesinkut Lake, Armstrong (1949, p. 70) collected fossil leaves

from rocks included under the general heading of the group which indicated
an Upper Cretaceous or later age. On the road north of Francois Lake, he
(1949, p. 73) collected fossil leaves from rocks belonging to this group that
were of Upper Eocene or Oligocene age.

In Nechako map-area north of Intata Lake, Tipper collected plant

remains from a rhyolite tuff at or near the top of the group. W. A. Bell who
studied the collection correlated them with the flora of the Kitsilano formation
of probable late Oligocene age.

This information along with the structural relations of the group indicates

that the period of deposition lasted from some time in the Upper Cretaceous
probably to late Oligocene time.