Electron microscopic studies on the thymus of the Arabian camel (Camelus dromedarius)

The thymus of young camels contained 2 main cell types: lymphocytes and epithelial reticular cells (ER). 3 types of ER cells were observed and described. 2 types from these cells showed secretory activities, meanwhile, the third type had well developed tonofilaments. Hassall's corpuscles were noted in the medulla and were composed of degenerative concentrically arranged ER cells. The functional morphology of the above mentioned structures was discussed.