[Metastasizing lymphosarcoma in a giant snake, Eunectes murinus (Linnaeus, 1758)].

This report of a tumor of the hematopoietic system in an anaconda snake, Eunectes murinus, is the first of such a growth in a reptile. The primary site was apparently in undifferentiated mesenchymal cells in the liver and secondarily deposits occurred in the thyroid, spleen, pancreas, and kidneys. The lymphoblast was the predominant cell type in all of these organs; hence the tumor is designated as a lymphosarcoma.