[Blood morphology of the European eel (Anguilla anguilla). II. Studies on granulopoiesis].

It was found that the granulocytes for Anguilla anguilla mainly form in the kidney. The stem cell of granulocytes is the large hemocytoblast. Sequences of development were established for the heterophil, cosinophil and basophil granulocytes. Myeloblasts, promyelocytes, metamyelocytes, mature red-shaped and segmented forms were described as stages of development of the heterophil granulocytes. In the case of the eosinophil and basophil granulocytes the myeloblastic and myelocytic stages could be demonstrated as well as the mature granulocyte. By the aid of special granular staining, phase contrast observations, supravital and cytochemical investigations the granulocytes could be described. The cytochemical proof for the granulocytes delivered a distribution pattern of the lipids, carbohydrates, RNA (RNS) and enzymes: unspecific esterase, alkaline and acid phosphatases, oxydase and peroxydase. By means of heart puncture a larger loss of blood was caused and the hematopoiesis stimulated. The following blood letting gave indications of how rapidly the granulopoiesis develops and how much time maturing takes. After a larger loss of blood the new-growth of the granulocytes will be completed nine days later.