(In one genus (Lactarius) milk-tubes, recalling the laticiferous tubes of many vascular plants, are found.) These elongated hyphae are frequently thick-walled, and in some cases form a central strand, which may serve to resist longitudinal pulling strains.
In certain families of Angiosperms a peculiar tissue, called laticiferous tissue is met with.
They possess a delicate Laticiferous layer of protoplasm, with numerous small nuclei lining Tissue the walls, while the interior of the tube (corresponding with the cell-vacuole) contains a fluid called latex, consisting of an emulsion of fine granules and drops of very various substances suspended in a watery medium in which various other substances (salts, sugars, rubber-producers, tannins, alkaloids and various enzymes) are dissolved.
The relation ~ of the laticiferous tissue to the assimi I lating cells under which they often end, and the fact that where this tissue is / richly developed the conducting paren ~ chyma of the bundles, and sometimes also 4 the sieve-tubes, are poorly developed, as well as various other facts, point to the conclusion that the laticiferous system has an important function in conducting plastic substances, in addition to acting as an excretory reservoir.
- Laticiferous tissue is of two kinds:
Of laticiferous tubes arises (Papaveraceae, Hevea, &c.).
2o.Laticiferous vessels from the cortex of the root Scoyzonera hispanica, tangential secf ion.
In some cases special secreting tissues, resin ducts, oil glands, laticiferous tissue, crystal sacs, &c., may be developed among the ordinary secondary vascular elements.
Cases of complete fusion occur in the formation of laticiferous vessels, and in the spiral, annular and reticulate vessels of the xylem.
Laticiferous Tissue.The laticiferous tissue consists of a network of branching or anastomosing tubes which contain a coagulable fluid known as latex.
The walls are pitted, and protoplasmic connections between the laticiferous tubes and neighboring parenchyma-cells have been seen.
There are two types of tissue: non-articulate and articulate.
Laticiferous vessels arise by the coalescence of originally distinct cells.
The rows of cells from which the laticiferous vessels are formed can be distinguished in many cases in the young embryo while still in the dry seed (Scott), but the latex vessels in process of formation are more easily seen when germination has begun.
(hot.) (1887); Scott, Development of Articulated Laticiferous Vessels, Quart.
(1882); On the Laticiferous Tissue of Man-rhot Glazsovii (the Ceark Rubber), Quart.
The latex is usually obtained from the bark or stem by making an incision reaching almost to the wood when the milky fluid flows more or less readily from the laticiferous vessels.
Instead of the axe or large knives which frequently inflicted serious damage to the trees, special small knives and prickers are now employed so constructed as to avoid injury to the tree through making a larger incision than is necessary, and without penetrating into the wood below the laticiferous layer.