Papilla circumvallata (100X)
In this section, you can see the third type of papilla, the papilla circumvallata. There are only 10-14 of these on the tongue and they're situated in a V-shaped groove at the posterior part of the dorsum (lat: dorsum = back).
Encircling the papilla, there is a narrow furrow that separates it from the adjacent epithelium. On both sides of this furrow, you can find taste buds (oval shapes). Serous acini are situated at the base of the papilla. Salivary ducts from these acini empties into the furrow that encircle the papilla. The basal lamina is seen as a light pink colored tissue below the serous acini.