The Indians consider them to belong to the same species with the oestrus that deposits its ova under the skin: to us the larvae of the former appeared more flattened than those of the latter.

Specimens of both kinds preserved in spirits were destroyed by the frequent falls they received on the portages." Dr.
Richardson's Journal.) The reindeer retire from the sea-coast in July and August, rut in October on the verge of the barren grounds and shelter themselves in the woods during the winter.

They are often induced by a few fine days in winter to pay a transitory visit to their favourite pastures in the barren country, but their principal movement to the northward commences generally in the end of April when the snow first begins to melt on the sides of the hills and early in May, when large patches of the ground are visible, they are on the banks of the Copper-Mine River.

The females take the lead in this spring migration and bring forth their young on the sea-coast about the end of May or beginning of June.

There are certain spots or passes well-known to the Indians, through which the deer invariably pass in their migrations to and from the coast and it has been observed that they always travel against the wind.