papyrus (pəpĪˈrəs) [key], a sedge ( Cyperus papyrus ), now almost extinct in Egypt but so universally used there in antiquity as to be the hieroglyphic symbol for Lower Egypt and a common motif in art. The roots were used as fuel; the pith was eaten. The stem was employed for sandals, boats, twine, boxes, mats, sails, cloth and most notably as a writing material (used in Egypt until the introduction of paper there in the 8th cent. and exported throughout the Mediterranean world). This writing material, which was also called papyrus, was formed into sheets by laying lengthwise slices of the sedge side by side in two layers at right angles and pressing them together with an adhesive probably composed of their own juices and Nile water. The sheets were glued end to end and rolled on wooden rods to form manuscripts. Many examples have been recovered, especially in Egypt, and have furnished valuable literary and historical matter in Greek and other languages. The science of papyrology is concerned with the study of these documents. Papyrus is classified in the division Magnoliophyta, class Liliopsida, order Cyperales, family Cyperaceae.