The structures of aggregates obtained in vitro from cell suspensions of locust embryos were studied by light microscope on Epon-sections. The aggregates show an internal pattern which is the result of a sorting out and a specific association of embryonic cells. True aggregates are formed. A general characteristic is that no outer cellular boundary and no inner mesenchyme-like structure are present. The size and the structure of the aggregates differ according to the developmental stage of the embryos which provide the cells. At the earlier stages aggregation occurs but cell association seems to be at random. With embryos just before or after blastokinesis different structures inside the aggregates are observed. At developmental stages when histological differentiation begins or is going, aggregation does not occur or consists mainly of clumps of cells.
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Con il contributo del Ministero per i Beni e le Attività Culturali