STRUCTURE OF CENTRAL NERVOUS SYSTEM OF A PULMONATE MOLLUSC (CRYPTOMPHALLUS ASPERSA) .I. ULTRASTRUCTURE OF CONNECTIVE EPINEURAL SHEATH

The connective epineural sheath of the abdominal mass ganglia of the land snail Cryptomphallus aspersa was studied by light and electron microscopy. In this sheath several cellular types were found: fibroblasts, macrophage cells, a special type rich in mitochondria; elongated cells which proved to be muscle cells of paramyosin type and glial cells with dense bodies in close contact with neurosecretory axons. Special attention was paid to the filaments of the muscle cells. Thin and thick ones were found, the last with cross bands with a repeating period of 150 Å. These findings are discussed in relation with the physiological role of the epineural connective sheath in metabolic and mechanical functions. © 1969 Springer-Verlag.