A clementine is the hesperidium of a variety of mandarin orange (Citrus reticulata), named in 1902. A clementine is an oblate, medium-sized citrus fruit. The exterior is a deep orange colour with a smooth, glossy appearance. Clementines separate easily into eight to fourteen juicy segments. They are very easy to peel, like a tangerine, but lack the tangerine's sourness and seeds. Clementines are also known as seedless tangerines, but sometimes contain seeds.