Illustration of the three-compartment stomach of a llama. The first compartment (C1) is the fermentation vat. Note the ventral saccules, which have a glandular epithelium. The second compartment (C2) seems to function similar to the reticulum of ruminants. The third compartment (C3) has both fermentative and acid-secreting regions, with the aborad portion functioning as a true stomach analogous to the abomasum. Adapted, with permission, from the Color Atlas of Large Animal Applied Anatomy by Hilary M. Clayton and Peter F. Flood, Mosby-Wolfe, 1996.