Sea hares with seeds have a big fat belly, while those without seeds only have two layers of skin.

Sea hare, also known as sea slugs, but the sea hare is neither a rabbit nor a slug, belonging to the shallow sea life of shellfish, is a mollusc, gastropods, bare gills of the order collectively, because of the head of the two pairs of tentacles protruding such as a rabbit's ear and so named.

It is a specialized member of the mollusk family. Their shells have degenerated into an inner shell. The back has a thin transparent shell skin, which is usually white and pearly.

The sea hare is a hermaphroditic creature that inhabits the sea floor with a naked body and an oospore groove connecting the two reproductive pores of the male and female. Sea hare is distributed in the warm sea area of the world, China's warm sea area is also produced. Sea hare is the first scientists found that can produce the plant pigment chlorophyll animal.