A. Anomalous, Fibrous, And Fibrocartilaginous Tissue

This tissue occurs a. Very often upon the surface of the organ underneath its peritoneal sheath, in the shape of smooth and level, or tuberculated plates, of varying thickness and size. It occurs in this shape at advanced periods of life, as a result of the congestion to which the parenchyma and the investment of the organ have been exposed. It is not very unusual to find these laminae of such an extent as to invest the entire convexity of the spleen, and to present a thickness of several (two, three, and five) lines.

fi. It occurs very rarely in the shape of fibroid tumors of the parenchyma of the spleen.

B. Anomalous Osseous Growths

We find them occurring a. As ossification of the fibroid laminae just described, of the same extent and thickness as the latter; they are rarely found except in very old people;

/3. As cretified fibrine in the cellulo-ftbrous callus, subsequent to primary and secondary inflammation of the spleen; y. As round unattached concretions, or phlebolithes, in the venous channels of the spleen.

E. Formation Of Cysts

Encysted tumors of the spleen are very remarkable, and as unusual as cancer, a fact which is interesting on account of the contrast with the frequency of tubercle. The acephalocyst is either found in the spleen alone, or concurrently with one in the liver; it rarely attains the size it reaches in the latter organ, but is otherwise not distinguished by any peculiarity. Cysts with other contents are still less frequent.

D. Tubercle

Tubercular disease affects the spleen only less frequently than the lungs and the lymphatic glands. It always characterizes an advanced stage of tuberculosis, which had previously only appeared as chronic disease in some other organ, as the lungs, the brain, or the lymphatic glands, or had merely existed in a latent form, and is now converted into acute general tuberculosis. Splenic tubercle is consequently always complicated with tubercle in the most various organs, and very frequently with universal tubercular deposit.

Tubercle of the spleen, when acute, commonly appears in the shape of numerous densely-sown granulations of the size of a pin's head or millet-seed, resembling gray transparent vesicles, or of an opaque white color; or as yellow cheesy masses, varying in size from a millet-seed to a pea. When chronic, it presents the shape of crude, originally gray, granulations of the size of a millet- or hemp-seed, which subsequently are converted into a cheesy substance.

The parenchyma of the spleen is the seat of tubercle; we not unfre-quently find a small central cavity within the tubercle, and the latter is occasionally surrounded by a cyst or capsule of fibro-lardaceous texture, a fact which demands special investigations for its elucidation.

For the same reasons that apply to hepatic tubercle, tubercle of the spleen scarcely ever passes beyond the stage of commencing ramollisse-ment.

The spleen appears swollen in proportion to the quantity, and also to the size of the tubercles: in acute tuberculosis its turgescence and the relaxation of its parenchyma strongly resemble the typhous condition.

E. Cancer

Cancer occurs very rarely; we have as yet only met with the medullary variety in combination with cancer of other organs, especially of the liver and the lumbar glands. The structure of the spleen appears to afford a satisfactory explanation of the fact, that cancer occurring in it is frequently invested by a fibrous sheath, within which it passes into a state of ichorous solution. The sheath is formed by the displaced fibrous tissue of the spleen, which, in the case of the adventitious growth attaining a considerable size, is strengthened by the fibrous investment of the spleen.