logical characters, and in containing the same
orthoceratite which was also found by Captains Parry and Lyon at
Igloolik.

The colour of the limestone of Lake Winipeg is very generally
yellowish-white, passing into buff, on the one hand, and into ash-gray
on the other. A reddish tinge is also occasionally observed. Much of it
has a flat fracture, with little or no lustre, and a fine-grained
arenacious structure. A great portion of it, however, is compact, and
has a flat conchoidal and slightly splintery fracture. This variety
passes into a beautiful china-like chert. [Sidenote: 1001, 1014] Many of
the beds are full of long, narrow vesicular cavities, which are lined
sometimes with calc-spar, but more frequently with minute crystals of
quartz. The beds of this formation seldom exceed a foot in thickness,
and are often very thin and slaty. The arenacious and cherty varieties
frequently occur in the same bed; sometimes they form distinct beds. The
softer kinds weather readily into a white marl, which is used by the
residents to whitewash their houses. Wherever extensive surfaces of the
strata were exposed, as in the channels of rivers, they were observed to
be traversed by rents crossing each other at various angles. The larger
rents, which were sometimes two yards or more in width, were however,
generally parallel to each other for a considerable distance.

Professor Jameson enumerates _terebratulae_, _orthoceratites_,
_encrinites_, _caryophyllitae_, and _lingulae_, as the organic remains in
the specimens brought home by Captain Franklin on his first expedition.
Mr. Stokes and Mr. James De Carle Sowerby have examined those which we
procured on the last expedition, and found amongst them
_terebratulites_, _spirifers_, _maclurites_, and _corallines_. The
maclurites belonging to the same species, with specimens from Lakes Erie
and Huron, and also from Igloolik, are perhaps referrible to the
_Maclurea magna_ of Le Sueur. [Sidenote: 1015, 1019] Mr. Sowerby
determined a shell, occurring in great abundance in the strata at
Cumberland-house, about one hundred and twenty miles to the westward of
Lake Winipeg, to be the _Pentamerus Aylesfordii_.

The extent to the westward of the limestone deposit of Lake Winipeg is
not well known to me; but I have traced it as far up the Saskatchewan as
Carlton House, and its breadth there is at least two hundred and eighty
miles. For about one hundred miles below Carlton House, the river
Saska