Illustration of the surface of the tongue, or lingual mucosa, showing two fungiform papillae (rounded) and filiform papillae, some with their protrusions extended and some with them folded inwards. Filiform papillae are the most abundant papillae and sense pressure. Fungiform papillae contain taste buds. From Traite dAnatomie Humaine, Vol 3 (1905) by French anatomist Leo Testut (1849-1925).