What type of monkeys do Bengal tigers eat?

Tigers are pure carnivores. They prefer hunting large ungulates such as chital, sambar, gaur, and to a small extent also barasingha, water buffalo, nilgai, serow and takin. Among the medium-sized prey species they frequently kill wild boar, and occasionally hog deer, muntjac and Gray langur. Small prey species such as porcupines, hares and peafowl are also hunted and form a very small part in their diet. Sometimes, they also prey on domestic livestock too that wander off into the jungles

They stay hidden and move near the unsuspecting prey. Once they are near enough, they pounce and take the prey down. They go for the throat and strangulate their prey. But they do eat one kind of monkey but I can't remember what it is called. P.S. I saw it in the movie Planet Earth.