LIST OF MAMMALIA,

Collected during Mr. Rae's Expedition, with Observations by J. E. Gray, Esq., F.R.S. &c.

1. Mus Musculus. Linn. York Factory. Probably introduced from Europe.

2. Arctomys Parryi. Richardson, Faun. Bor. Amer. p. 158, tab. 10.

3. Lepus Glacialis. Leach. Richardson, Faun. Bor. Amer. 221.

Myodes.—The specimens brought by the expedition have enabled me to make some corrections in the characters assigned to these species. I may observe that the large size or peculiar form of the claws which has been regarded as a character of the species, appears to be peculiar to one sex—probably the males.

1. The upper cutting teeth narrow, smooth without any longitudinal groove. Thumb with a compressed curved acute claw. (Lemnus).

Myodes, Lemnus Pallas. Glires 77 of Sweden.

Myodes Helvolus. Richardson, Faun. Bor. Amer. p. 128, belong to this section. All the museum specimens of these species have small, simple, curved, acute claws.

4. Myodes Hudsonius. Richardson, Faun. Bor. Amer. 132.

Grey, black washed beneath white, sides reddish, sides of the neck red, nose with a central black streak, claws of male(?) very large, compressed, equal, broad to the end, and notched; of female small, acute. In winter with very long black white-tipped hairs. Mr. Rae brought home two males, one in winter and one in change fur, and two females in summer fur.

5. Myodes Greenlandicus.

Reddish-grey, brown, black varied, back with a longitudinal black streak, beneath grey brown, chest, nape, and sides ruffous. Front claw of males(?) compressed, curved, the under surface (especially of the middle one) with a broad, round, expanded tubercle. I have not seen this species showing any change in its winter fur.

2. Upper cutting teeth broader, with a central longitudinal groove. The claw of the front thumb strap-shaped, truncated, and notched at the tip.

6. Myodes Helvolus. Richardson, Faun. Bor. Amer. 128. (female?)

Fur very long, black, grey-brown; black grizzled, hinder part of the body reddish, beneath grey, sides yellowish. Claws of the fore feet (of the males?) large, thick, rounded, curved, bluntly truncated at the tip; of the female compressed, curved, acute.

7. Myodes Trimuconatus. Richardson, Faun. Bor. Amer. 130.

Bright red brown, head blackish-grey, sides and beneath pale ruffous, chin white, claws moderate, compressed. This species is best distinguished from the former by its larger size and the great brightness of the colour, and the fur being much shorter and less fluffy.