Some portions of this rock contain very perfect shells.

With respect to the vegetable productions of the district the Populus trepida, or aspen, which thrives in moist situations, is perhaps the most abundant tree on the banks of the Saskatchewan and is much prized as firewood, burning well when cut green.

The Populus balsamifera or taccamahac, called by the Crees matheh meteos, or ugly poplar, in allusion to its rough bark and naked stem, crowned in an aged state with a few distorted branches, is scarcely less plentiful.

It is an inferior firewood and does not been well unless when cut in the spring and dried during the summer; but it affords a great quantity of potash.

A decoction of its resinous buds has been sometimes used by the Indians with success in cases of snow-blindness, but its application to the inflamed eye produces much pain.