Investigation of the presence of chromaffin tissue in the ovary of the percoid teleost fish, Nandus.

The ovary of Nandus shows chromaffin tissue at different sites below the tunica albuginea, along the ovigerous lamellae and near the oocytes. The tissue can be mistaken for interstitial cells as it shows intense sudanophilia. That it is chromaffin tissue is confirmed by its positive reaction to all the usual histochemical tests for chromaffin. This tissue may represent some stage in the development of "corpora lutea".