Morphology of the nervous and muscular systems in the heads of pedicellariae from the sea urchin Echinus esculentus L
Article first published online: 6 FEB 2005
Copyright © 1987 Wiley-Liss, Inc.
Journal of Morphology
Volume 193, Issue 1, pages 35–51, July 1987
How to Cite
Peters, B. H. and Campbell, A. C. (1987), Morphology of the nervous and muscular systems in the heads of pedicellariae from the sea urchin Echinus esculentus L. J. Morphol., 193: 35–51. doi: 10.1002/jmor.1051930105
- Issue published online: 6 FEB 2005
- Article first published online: 6 FEB 2005
Light and electron microscopy reveal that simple receptor cells in the jaw epithelium of sea urchin pedicellariae are connected by nerve tracts to the neuropile that coordinates jaw movements. The muscles responsible for jaw opening and closure and for flexion of the stem are all innervated in this neuropile. At least two types of vesicles occur at the simple synapses between neurone profiles and at neuromuscular junctions. The muscles include both striated and smooth fibres; however, their distribution varies according to pedicellaria type, and an unexpected arrangement exists in trifoliate pedicellariae.