Summary
The radial nerve cords of a number of different species of echinoids and asteroids have been examined with the electron microscope. They have been shown to consist of tracts of small naked axons with discrete regions of neuropile. Synapses within these areas of neuropile have been described and their significance discussed. A careful examination has failed to reveal any connections between the ectoneural nerve and the mesodermal nerves and muscles. Synapses across the connective tissue sheet separating these regions have been proposed to account for known functional connection. A hypothetical model of the nervous system has been proposed to account for known structure and function.
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The author wishes to acknowledge the help of Prof. M. S. Laverack during this study. Part of this work was carried out while the author was in receipt of a Queen Elizabeth Fellowship from the Commonwealth Government of Australia.
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Cobb, J.L.S. The significance of the radial nerve cords in asteroids and echinoids. Z. Zellforsch. 108, 457–474 (1970). https://doi.org/10.1007/BF00339653
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DOI: https://doi.org/10.1007/BF00339653