As a rule, the teeth of the two sides of the jaws are alike in number and character, except in cases of accidental or abnormal variation, and in the tusks of the narwhal, in which the left is of immense size, and the right rudimentary.
The name "sea-unicorn" is sometimes applied to the narwhal.
The narwhal and the beluga have a very similar distribution, though the latter occasionally ranges farther south.
The white whale fishery of the Eskimo, however, continued, and sealing is important; walruses are also caught and sometimes narwhal.
Among them is the narwhal tusk used as a walking cane by Captain John Wood, who owned a fleet of whalers.