Snails consist of thousands of different species and consume a wide variety of different diets, although most land snails are herbivorous. For example, the common garden snail consumes cultivated plants, including citrus, while the geography cone snail is a predator of fish. Some snails even prey upon other snails.
The garden snail, Cornu aspersum, eats both the leaves and fruit of citrus trees, as well as the leaves of many other domestic plants. These snails are about an inch long and are considered serious pests in large numbers. The giant African snail, by contrast, grows up to 10 inches in length and has a large appetite for fruit and leaves. Some freshwater species of snail, such as the apple snail, consume algae and are popular in aquariums. The marine-based geography cone snail hunts fish by engulfing or spearing them with a specialized spine.