THE HEMATOCYTOGENESIS IN LEIOCASSIS LONGIROSTRIS

The Wrigh-t Giemsa and PAS stained imprints and smears of hematopoietic organs were observed by the light microscopy. The results showed that the head kidney, body kidney and spleen were the principal hematopoietic organs. Erythrocytes,lymphocytes and granulocytes developed mainly in head kidney and body kidney, and some of them developed in spleen.While most of monocytes developed in body kidney and spleen, some of them in head kidney. No primit ive blood cells were observed in liver smears, so liver was not a hematopoietic organ.The erythroid lineage consisted of proerythroblast, basophilic erythroblast, acidophilic erythroblast and erythrocyte. During maturation of the erythroid cells, two trends in size were distinguished: two decreasing and one increasing. Due to the great changes of granuloid cells in maturation, the granuloid lineages were divided into five stages: granuloblast, young granulocyte,progranulocyte, metagranulocyte and granulocyte. During the maturation of granuloid cells, they were reduced in size. The peripheral blood was the final place for their development. Maybe the bilobed granulocytes were ageing or senile granulocytes and the split of nucleus was a sign of senility. The lymphoid lineages were divided into three stages: lymphoblast, prolymphocyte and lymphocyte. The development of mononuclear cells was similar to that of lymphoid cells. They experienced three stages respectively: monoblast, promonocyte and monocyte. These two kinds of cells regularly reduced in size during development. Macrophages were derived from monocyte and they had phagocytosis. The primitive blood cells and some early immature blood cells all had mitotic activity. Some bilobed erythrocytes and bilobed thrombocytes could be observed and were considered to be cells in amitotic division. Precursors of thrombocytes were not encountered.During all the stages of the erythroid lineage, the erythroid cells were all PAS negative. While during the development of leucocytes, the cells were from negative to positive with PAS staining, and it suggested that with the maturing of the leucocytes the contents of glycogen were increasing gradually.