Chelonians may be carnivorous, herbivorous or omnivorous in feeding habits. Aquatic turtles are chiefly carnivorous reptiles feeding on snails, fish, mice, slugs, worms and insects. Lettuce or other plant material is occasionally given to captive aquatic turtles. The captive diet is also supplemented with liver oil or vitamins containing A, D and E. Aquatic turtles swallow foods with their heads submerged in water. The marine turtles subsist on fish, invertebrates and sea weed. Many adult sea turtles are virtually herbivorous. The box turtle is omnivorous in feeding habit and can be offered worms, snails, lettuce, tomatoes, mouse pups, melons, fruits and cottage cheese. The olive ridley turtle is also omnivorous in feeding habits. They feed on dead fish, crabs and other crustaceans, and soft parts of mollusks. The green turtle is herbivorous and feeds on sea algae (e.g. GraciIlana sp and Gelidiella acerosa) and sea grass (e.g. Cymodacea sp). The hawksbill turtle is largely carnivorous animal. They feed on sponges and other invertebrates, and fish. The leathery turtle primarily feeds on jelly fish. In captivity, tortoises eat flowers and leaves mixed with succulent grasses, carrots, green peas, fruits, pumpkins, tomatoes and melons. A small amount of bread or dog food may be given. Food materials should be placed on dry land for ground living tortoises. Larger aquatic turtles may be fed thrice or less a week. However, some authors are of the opinion that as most aquatic turtles do not tend towards obesity, food may be provided daily. Young turtles, however, should be fed daily. Young can grow well on a commercially prepared feline diet.