== Thymus ==

The thymus is unlike other lymphatic organs in two major respects: (1) its stroma consists of a framework of connecting epithelial reticular cells (cytoreticular cells) derived from endoderm. This stroma is not typical reticular connective tissue that is derived from mesoderm and characteristic of other lymphatic organs. (2) Lymphatic nodules are lacking, but the organization of the lobules into a cortex and a medulla may give the unwary student the impression that nodules are present.

<peir-vm>UAB-Histology-00059</peir-vm>

== Tonsils ==