Cats

There were ten Black Cats and one White cat who helped Beruthiel spy on the people of Gondor. Beruthiel wanted to spy because she was evil an was of Black Numenoreans descent. Note that the Black Numenoreans were ancient enemies of Gondor, and hasted its people. They fought under Sauron.

Black Cats
The Black Cats that Queen Beruthiel owned were evil-looking. They did not hide that they were spying on the Gondorians. There were 10 of them. After Queen Beruthiel was sent off in a small boat by Tarannon Falastur, the Black cats accompanied her. Note that Queen Beruthiel did not trust her cats.

White Cat
The White Cat of Queen Beruthiel was more evil than the black cats. Since Beruthiel did not trust her black cats, she ordered her white cat to spy on them. The white cat did a good job of spying, because the black cats never found out that they were being watched.

Cats of the West
Several Other Cats were mentioned by Tolkien. They included a cat sang in a song by Frodo in Bree, as well as a cat owned by Bob, Hobbit of Bree. When Bilbo Baggins was playing a riddle-game with Gollum, This Riddle was given: "No-legs lay on one-leg, two-legs sat near on three-legs, four-legs got some." = "Fish on a little table, man at table sitting on a stool, the cat has the bones."