Latex

Latex, a milky emulsion occurring in special secretive structures in many plants. It is generally white, and its abundance gives the name Lactarius to a genus of fungi allied to the agarics. In Chelidonium it is orange, and among Dicotyledons its abundance is characteristic of the orders Moraceas, Euphorbiacese, Sapotaoeae, and Papavcracea?, and the sub-order Liguliflora of the Compositae (q.v.). It occurs either in rows of small cells, as in the elder; in cells which grow to a large size and braucli with the growth of the plant from the seed stage, as in some Euphorbiacete; or in a system of branching and anastomosing laticifcrous vessels. These are generally in the bast region of the stem; but. may also be in the young wood or pith. The fluid is mainly water with alkaloid in solution, and solid particles of-rubber and albuminoid matter in suspension. In physiology (q.v.) its function appears to be the conveyance of the "elaborated sap" from the leaves. Gutta, rubbers, and many medicinally -valuable alkaloids are among the products of the latex.