title: [Cytological study of the hemopoietic organ in the crab: Carcinus maenas (L.) (Crustacea, Decapoda). (author's transl)].
abstract: A cytological observation, using conventional fixing and staining, is made on the hemopoietic tissue in the crab, Carcinus maenas. The hemopoietic organ is formed by nodules grouping different cell types; nodules are surrounded by a limiting layer including collagenous filaments and material looking like basal lamina. Some fibrocytes and semi-granulous hemocytes are lining this limited layer. These hemocytes, more or less flattened, are transforming in fibrocytes. Fibroblast-like cells, with well developed intercellular junctions, are the first cell type: their dedifferentiation gives rise to isolated mitoting cells. We have named these mitoting cells "hemocytoblast". They are stem cells for hyaline hemocytes. Fibroblast-like cells can be compared with "reticular cells" in Insects. Uncertainty exists as to the formation and evolution of nodules.
mesh_terms: D000818:Animals; D001773:Blood Cells / Q000166:cytology*; D003386:Brachyura / Q000166:cytology* / Q000502:physiology; D002462:Cell Membrane / Q000648:ultrastructure; D002467:Cell Nucleus / Q000648:ultrastructure; D003593:Cytoplasm / Q000648:ultrastructure; D005260:Female; D005347:Fibroblasts / Q000648:ultrastructure; D006410:Hematopoiesis; D006434:Hemocytes / Q000166:cytology*; D008297:Male; D008938:Mitosis; D009940:Organoids / Q000648:ultrastructure
vernacular_title: Ultrastructure de l'organe hématopoïétique chez le crabe Carcinus Maenas (L.) (Crustacea, Decapoda).