The white pulp is composed of spherical aggregates of lymphocytes (lymphatic nodule (LN)) with a lighter staining germinal center and an outer, relatively thin, darker stained marginal zone, which separates white pulp from red pulp. Thick-walled central arteries are usually evident penetrating the white pulp. The central artery is cut obliquely in the white pulp at the upper left. Two arteries are seen penetrating the nodule in the center-left of the field and a single artery penetrating the white pulp in the lower-center of the field. The central artery is often seen in the lymphatic nodule in an eccentric position. It has no afferent lymphatics.