The blood cells and their precursors in the hemopoietic organs of the dogfish Scyliorhinus stellaris

The AA. study the morphocytochemistry of the blood cells and their precursors, on smears of circulating blood and on imprints of spleen, oseophageal and epigonal lymphomyeloid tissues of Scyliorhynus stellaris L. On the basis of their morphology and of the results observed with the 15 cytochemical reactions performed, the AA. identify in circulating blood: lymphocytes, plasmocytes, monocytes, neutrophilic granulocytes type 1° and 2°; eosinophilic granulocytes type 1° and 2° and thrombo¬cytes, with their own characteristics and without transitional forms between them. On the imprints of lymphomyeloid tissues they find that erythropoiesis occurs mainly in the spleen but erythroblasts pass into circulating blood; lymphocytopoiesis occurs mainly in the' spleen; neutrophilic granulocytopoiesis type 1 ° occurs mainly in the epigonal tissue; eosinophilic granulo-cytopoiesis type lc occurs in the spleen; eosinophilic granulocytopoiesis type 2° occurs both in the oesophageal and epigonal tissues