Woodcut of a "marine monster resembling a Bishop dressed in his pontifical garments" from Des Monstres et prodiges by Ambroise Par矇, 1573. Des Monstres is filled with unsubstantiated accounts of sea devils, marine sows, and monstrous animals with human faces. With its extensive discussion of reproduction and illustrations of birth defects, the book invited accusations of pornography. Sea monsters are sea-dwelling mythical or legendary creatures, often believed to be of immense size. Marine monsters can take many forms, including sea dragons, sea serpents, or multi-armed beasts. They can be slimy or scaly and are often pictured threatening ships or spouting jets of water.