The Monotremata are a bit of a biological oddity, as they are the only group of mammals to lay eggs rather than give birth to live young. The Monotremata alive today are all found in Australia and New Guinea and consist of four species of echidna and the platypus. The latter is well known for its unusual appearance, as the platypus has a bill like a duck, a tail like a beaver, and feet like an otter.
![Les Ammonites du Lias Inferieur (Hettangien et Sinémurien): Inventaire et Classification [Ammonites of the Lower Lias (Hettangian and Sinemurian): Inventory and Classification]](http://mediacdn.nhbs.com/jackets/jackets_resizer_medium/26/268266.jpg?height=150&width=105)
![Uma Coleção de Orquídeas – Cattleya, Espécies Bifoliadas Brasileiras, Volume 4 [A Collection of Orchids – Cattleya, Brazilian Bifoliate Species, Volume 4]](http://mediacdn.nhbs.com/jackets/jackets_resizer_medium/26/262231.jpg?height=150&width=108)
