NEW YORK WEASEL IN WINTER
A blood-thirsty cousin of the Otter and the Mink. Range: This and related species found all over United States and Canada. Group in American Museum of Natural History.
In their food habits many mammals are decidedly injurious. Rats, Weasels, Minks, and Foxes destroy poultry; Wolves and Pumas kill domestic and game animals; Woodchucks or Groundhogs eat clover and various garden plants; Moles damage the lawns; Rats, Mice, and Gophers spoil and devour grain; Mice and Rabbits girdle fruit trees, thus killing them.
RACCOON AT ENTRANCE TO ITS DEN IN A HOLLOW TREE
A near relative of the bears. Note the black face-mark and the ringed tail. Range: This or a related variety occurs in all parts of United States. Photograph from American Museum of Natural History.
On the other hand, many mammals furnish food; e. g., Rabbits, Elk, and Deer. This was more important in pioneer times than at present. Many furnish furs used as articles of clothing; e. g., Raccoon, Fox, Muskrat, Mink, Otter, Marten, Mole, New York Weasel and other northern weasels in their winter coats.
POLAR BEAR
An expert swimmer. Feeds upon seals, fish and other animal food. Range: Arctic regions of the world. Habitat Group in American Museum of Natural History.
Many furs are usually sold under trade names that are entirely different from the true name of the animal. A list of a few fur-bearing mammals of the United States having trade names differing from the true names follows:
| The True Fur | The Trade Name |
| Dark blended Muskrat | Russian Otter |
| Mink blended Muskrat | Natural River Mink |
| Natural Muskrat[6] | River Mink |
| Natural Jersey Muskrat | River Sable |
| Plucked and Seal-dyed Muskrat | Hudson Seal |
| Plucked and Seal-dyed Muskrat | Aleutian Seal |
| Skunk | Black Marten |
| Striped Skunk | Civet Cat |
| N.Y. Weasel in winter pelage | Ermine |