The Contents Of Simple And Compound Cysts properly consist of a viscid fluid, in some cases translucent and colorless, in others, of a reddish tint. In compound cysts, these two conditions often alternate one with the other.

Some contain in and along with the said fluid, granules in various numbers, even to thorough repletion; some, together with these, clear, reddish-shaded vesicles, the size of a nucleus. Others contain granulated, spherical, oval nuclei.

The fluid contents of certain cysts appear denser, less transparent, opalescent; of others, still denser, dully transparent, presenting at the same time a marked cloudiness. In others, again, the density is still further marked, and the cloud more sharply defined.

This cloud results from a parting of the contents into spherical corpuscles, and flaky pellets of various size. In a given cyst it seems tolerably uniform, or else it consists in a radius-like Assuring from the periphery towards the centre of the cyst. In compound cysts, the separation differs in degree and relative amount in the individual cysts, being often more developed, either in the outer or in the inner cysts, and in one or other not present at all.

The Assuring presents much that merits attention. In simple vesicles or cysts, it extends from the periphery towards the centre, where the radii or the points of the wedges of substance, bordered by the fissures, converge. In compound cysts, a fissure present in the external vesicle, borders either upon the contour of a nucleolus, of a nucleus, or of the secondary cyst, in which, if there be a Assuring, it is independently constituted. Or again, the fissure-lines of the cysts correspond with one another - in other words, the fissure affecting the external cyst is prolonged through the second, third, fourth inner cysts, etc, with a radius common to all. This is rendered possible by the metamorphoses of the cyst-wall about to be explained.

With the condensation of its contents, the wall of the cyst gradually disappears, seemingly blending with the contents to a uniform mass. As in the case of the so-called cysts of the vascular plexus, the entire cyst is transformed into a dull, opalescent, resilient, simple or compound, colloid globule, which splits under the covering glass plate, - a spherical, oval, cylindrical, or nodulated colloid mass. To this category, doubtless belong the unexplained bodies seen by Kohlrausch in a renal cyst. (Vogel, Path. Anat).

This relation of the cyst-wall further determines the contents, reduced, after the completed process of separation, to an aggregate of stellate flocculi, which break up into roundish, opalescent fragments of various size. There are always present globular debris from which numerous fragments of this kind have become separated.

This relation of the cyst-wall occasions the breaking up of the already fissured contents, either spontaneously, or from pressure, into stratiform, or wedge-like fragments, as is particularly frequent in in-crusted specimens. The same cause produces the linear disruption, through pressure of the smooth compound colloid sphere, athwart many of its strata. These formations, together with the remaining amorphous colloid contents of the cyst, are sometimes tinged of a brownish or of a yellow hue, from imbibed pigment.

An ulterior change in these formations, which should here be noticed, is their incrustation with phosphate and carbonate of lime. It commonly affects the compound laminated cysts, but not unfrequently, the simple ones also; the comprehensive, equally with the small ones; the smooth, equally with the gibbous. It invariably emanates in the simple cysts from the centre, in the compound, from the central layer, whether this consist of a simple nucleus, or a group of nuclei in a vesicular nucleus-development. The secondary cysts lying side by side within a simple or a compound cyst, become incrusted independently of each other, and also of the parent cyst. The cysts affected with incrustation are those whose contents have undergone the condensation before referred to.

Lastly, many cysts contain granules and globules, which are shown to be of a fatty nature, the cyst resembling in some sort a colossal granule-cell.

(d.) There is in the primary and secondary formations within the cysts hitherto spoken of, frequently a colorless hyaline, or colored colloid substance, in the shape of roundish, oval, facetted, poppy-seed, millet-seed, or lentil-sized pellets and flakes, and of larger misshapen masses. It is uniform in character with the opalescent, self-separating contents of the aforesaid microscopic cysts.