In the cross section of the |spleen| may be seen the various coats and layers of splenic tissue. The |spleen| is covered by an external, serous coat which lubricates the outside of the |spleen| with serous fluid to protect it against friction against the other viscera. Immediately within the serous coat, and adherent to it, is the internal, fibrous coat of the |spleen|. It forms the framework of the organ and follows the vessels within the |spleen|, forming sheaths around them. From these sheaths extend the fibrous bands, or trabeculae, which bind the sections of the |spleen| together, much as the |fibers| of a sponge. The sacs thus enclosed are called areolae, and within the areolae is the pulpy tissue of the |spleen|. This pulpy tissue is a reddish-brown, and is where the ~blood~ is filtered to remove bad cells, convert their ~hemoglobin~ to bilirubin, and return the iron from the destroyed cells back to the bloodstream.
